The heart of the server side is the Connector, and it is through the Connector that the server side of a transport is configured. The central goals of configuration on the server side are to establish a server invoker and supply it with a set of invocation handlers. Only one invoker can be declared per Connector. Although declaring an invocation handler is not required, it should only be omitted in the case of declaring a callback server that will not receive direct invocations, but only callback messages. Otherwise client invocations can not be processed. The invocation handler is the only interface that is required by the remoting framework for a user to implement and will be what the remoting framework calls upon when receiving invocations.

There are two general approaches to server side configuration: programmatic and declarative. A variety of programmatic techniques work in any environment, including the JBoss Application Server (JBossAS). Moreover, JBossAS adds the option of declarative configuration. In particular, the SARDeployer (see The JBoss 4 Application Server Guide on the labs.jboss.org web site) can read information from a *-service.xml file and use it to configure MBeans such as Connectors.

String locatorURI = "socket://test.somedomain.com:8084";
String params = "/?clientLeasePeriod=10000&timeout=120000";
locatorURI += params;
InvokerLocator locator = new InvokerLocator(locatorURI);
Connector connector = new Connector(locator);
connector.create();
SampleInvocationHandler invocationHandler = new SampleInvocationHandler();
connector.addInvocationHandler("sample", invocationHandler);
connector.start();

String locatorURI = "socket://test.somedomain.com:8084";
String params = "/?clientLeasePeriod=10000";
locatorURI += params;
InvokerLocator locator = new InvokerLocator(locatorURI);
HashMap config = new HashMap();
config.put(ServerInvoker.TIMEOUT, "120000");
config.put(ServerInvoker.SERVER_SOCKET_FACTORY, new MyServerSocketFactory());
Connector connector = new Connector(locator, config);
connector.create();
SampleInvocationHandler invocationHandler = new SampleInvocationHandler();
connector.addInvocationHandler("sample", invocationHandler);
connector.start();

String locatorURI = "socket://test.somedomain.com:8084";
String params = "/?clientLeasePeriod=10000";
locatorURI += params;
InvokerLocator locator = new InvokerLocator(locatorURI);
HashMap config = new HashMap();
config.put(ServerInvoker.TIMEOUT, "120000");
Connector connector = new Connector(locator, config);
connector.create();
ServerInvoker serverInvoker = connector.getServerInvoker();
ServerSocketFactory ssf = new MyServerSocketFactory();
serverInvoker.setServerSocketFactory(ssf);
SampleInvocationHandler invocationHandler = new SampleInvocationHandler();
connector.addInvocationHandler("sample", invocationHandler);
connector.start();

HashMap config = new HashMap();
config.put(ServerInvoker.TIMEOUT, "120000");
Connector connector = new Connector(config);

// Set xml configuration element.
StringBuffer buf = new StringBuffer();
buf.append("<?xml version=\"1.0\"?>\n");
buf.append("<config>");
buf.append("   <invoker transport=\"socket\">");
buf.append("      <attribute name=\"serverBindAddress\">test.somedomain.com</attribute>");
buf.append("      <attribute name=\"serverBindPort\">8084</attribute>");
buf.append("      <attribute name=\"clientLeasePeriod\">10000</attribute>");
buf.append("   </invoker>");
buf.append("   <handlers>");
buf.append("      <handler subsystem=\"mock\">");
buf.append("         org.jboss.remoting.transport.mock.SampleInvocationHandler");
buf.append("      </handler>");
buf.append("   </handlers>");
buf.append("</config>");

ByteArrayInputStream bais = new ByteArrayInputStream(buf.toString().getBytes());
Document xml = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(bais);
connector.setConfiguration(xml.getDocumentElement());

connector.create();
connector.start();

HashMap config = new HashMap();
config.put(ServerInvoker.TIMEOUT, "120000");
Connector connector = new Connector(config);

// Create ServerConfiguration object for socket transport
ServerConfiguration serverConfig = new ServerConfiguration("socket");

// Add invokerLocatorParameters (applicable to client and server)
Map locatorConfig = new HashMap();
locatorConfig.put("serverBindAddress", "test.somedomain.com");
locatorConfig.put("serverBindPort", "8084");
serverConfig.setInvokerLocatorParameters(locatorConfig);

// Add serverParameters (applicable to server)
Map serverParameters = new HashMap();
locatorConfig.put("clientLeasePeriod", "10000");
serverConfig.setServerParameters(serverParameters);

// Add invocation handlers
Map handlers = new HashMap();
handlers.put("mock", "org.jboss.remoting.transport.mock.SampleInvocationHandler");
serverConfig.setInvocationHandlers(handlers);

connector.setServerConfiguration(serverConfig);
connector.create();
connector.start();

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">
   <attribute name="InvokerLocator">
      <![CDATA[socket://test.somedomain.com:8084]]>
   </attribute>
   <attribute name="Configuration">
      <config>
         <handlers>
            <handler subsystem="mock">
               org.jboss.remoting.transport.mock.MockServerInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
</mbean>

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">
   
   <attribute name="Configuration">
      <config>
          
         <invoker transport="socket">
            <attribute name="numAcceptThreads">1</attribute>
            <attribute name="maxPoolSize">303</attribute>
            <attribute name="clientMaxPoolSize" isParam="true">304</attribute>
            <attribute name="socketTimeout">60000</attribute>
            <attribute name="serverBindAddress">192.168.0.82</attribute>
            <attribute name="serverBindPort">6666</attribute>
            <attribute name="clientConnectAddress">216.23.33.2</attribute>
            <attribute name="clientConnectPort">7777</attribute>
            <attribute name="enableTcpNoDelay" isParam="true">false</attribute>
            <attribute name="backlog">200</attribute>
         </invoker>
         
         <handlers>
            <handler subsystem="mock">
               org.jboss.remoting.transport.mock.MockServerInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
   
</mbean>

<attribute name="InvokerLocator">
   <![CDATA[socket://test.somedomain.com:8084/foo/bar]]>
</attribute>

<attribute name="Configuration">
   <config>
      <invoker transport="socket">
         <attribute name="serverBindAddress">test.somedomain.com</attribute>
         <attribute name="serverBindPort">8084</attribute>
         <attribute name="path">foo/bar</attribute>
      </invoker>
      ...

<?xml version="1.0" encoding="UTF-8"?>
<deployment xmlns="urn:jboss:bean-deployer:2.0">
            
   <bean name="remoting:invocationHandler"
         class="org.jboss.remoting.transport.mock.SampleInvocationHandler"/>
             
   <bean name="remoting:serverConfiguration"
         class="org.jboss.remoting.ServerConfiguration">
      <constructor>
         <parameter>socket</parameter>
      </constructor>
      <property name="invokerLocatorParameters">
         <map keyClass="java.lang.String" valueClass="java.lang.String">
            <entry>
               <key>serverBindAddress</key>
               <value>test.somedomain.com</value>
            </entry>
            <entry>
               <key>serverBindPort</key>
               <value>8084</value>
            </entry>
         </map>
      </property>
      <property name="serverParameters">
         <map keyClass="java.lang.String" valueClass="java.lang.String">
            <entry>
               <key>clientLeasePeriod</key>
               <value>10000</value>
            </entry>
         </map>
      </property>
      <property name="invocationHandlers">
         <map keyClass="java.lang.String" 
              valueClass="org.jboss.remoting.ServerInvocationHandler">
            <entry>
               <key>mock</key>
               <value><inject bean="remoting:invocationHandler"/></value>
            </entry>
         </map>
      </property>
   </bean>
             
   <bean name="remoting:connector" class="org.jboss.remoting.transport.Connector">
      <property name="serverConfiguration">
         <inject bean="remoting:serverConfiguration"/>
      </property>
   </bean>
             
</deployment>

Invoker configuration on the client side parallels configuration on the server side, with the exception that (1) it operates in a simpler environment (in particular, it does not assume the presence of an MBeanServer) and (2) it does not support a declarative option. However, it does support versions of the first three server side programmatic options, with the Client class playing the central role played by the Connector class on the server side.

Again, the most straightforward form of configuration is to put the configuration parameters on the InvokerLocator. For example, the fragment

String locatorURI = "socket://test.somedomain.com:8084";
String params = "/?clientMaxPoolSize=10&timeout=360000";
locatorURI += params;
InvokerLocator locator = new InvokerLocator(locatorURI);
Client client = new Client(locator);
client.connect();

creates a Client using the socket transport to connect to a server on host test.somedomain.com, listening on port 8084. It also passes in two parameters, "clientMaxPoolSize" and "timeout", that will be used by the client invoker.

It is also possible to use configuration maps on the client side. The following code fragment accomplishes all that the previous fragment does, but it passes one parameter by way of the InvokerLocator and passes the other by way of a configuration map. It also passes in a non-string object, a SocketFactory:

String locatorURI = "socket://test.somedomain.com:8084";
String params = "/?clientMaxPoolSize=10";
locatorURI += params;
InvokerLocator locator = new InvokerLocator(locatorURI);
HashMap config = new HashMap();
config.put(ServerInvoker.TIMEOUT, "360000");
config.put(Remoting.CUSTOM_SOCKET_FACTORY, new MySocketFactory());
Client client = new Client(locator, config);
client.connect();

Note that the value of ServerInvoker.TIMEOUT is "timeout", and the value of Remoting.CUSTOM_SOCKET_FACTORY is "customSocketFactory". These configuration map keys are discussed throughout the chapter and accumulated in section Configuration by properties. Also, socket factory configuration is covered in Socket factories and server socket factories.

Finally, a third programmatic option is available for those configuration properties which happen to be settable client invoker properties. In the following fragment, the client invoker is obtained from the Client and a SocketFactory is passed to it by way of a setter method:

String locatorURI = "socket://test.somedomain.com:8084";
String params = "/?clientMaxPoolSize=10";
locatorURI += params;
InvokerLocator locator = new InvokerLocator(locatorURI);
HashMap config = new HashMap();
config.put(ServerInvoker.TIMEOUT, "360000");
Client client = new Client(locator, config);
client.connect();
SocketFactory sf = new MySocketFactory();
ClientInvoker clientInvoker = client.getInvoker();
clientInvoker.setSocketFactory(sf);
      

Note. The Client creates the client invoker during the call to Client.connect(), so this option only works after that method has been called.

Note. Preference is given to values in the InvokerLocator. For example, in

String locatorURI = "socket://test.somedomain.com:8084/?clientMaxPoolSize=10";
InvokerLocator locator = new InvokerLocator(locatorURI);
HashMap config = new HashMap();
config.put("clientMaxPoolSize", "20");
Client client = new Client(locator, config);
      

the value of the variable clientMaxPoolSize would be set to 10. As of release 2.5.2, that behavior can be reversed by setting the parameter org.jboss.remoting.Remoting.CONFIG_OVERRIDES_LOCATOR (actual value "configOverridesLocator") to true. As always, in determining the value of the variable configOverridesLocator, preference is given to the InvokerLocator. But if the value of "configOverridesLocator" is set to true in the InvokerLocator, or if "configOverridesLocator" is absent from the InvokerLocator but it is set to "true" in the configuration map, then preference will be given to values in the configuration map. For example, in

String locatorURI = "socket://test.somedomain.com:8084/?clientMaxPoolSize=10";
InvokerLocator locator = new InvokerLocator(locatorURI);
HashMap config = new HashMap();
config.put("clientMaxPoolSize", "20");
config.put("configOverridesLocator", "true");
Client client = new Client(locator, config);
      

the value of the variable clientMaxPoolSize would be set to 20.

A number of transport independent features are introduced in Remoting version 2.4.

socket://10.32.4.2&192.168.4.2:6500

socket://multihome/?homes=10.32.4.2:6500!192.168.4.2:6500

socket://multihome:6500/?homes=10.32.4.2!192.168.4.2

socket://multihome:6500/?homes=10.32.4.2!192.168.4.2:6501

socket://multihome/?homes=10.32.4.2:6500!192.168.4.2:6501
       &connecthomes=10.32.42.2:7500!192.168.42.2:7501

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">
    
   <attribute name="Configuration">
      <config>
         <invoker transport="socket">
            
            <attribute name="homes">
               <home>10.32.4.2:6500</home>
               <home>192.168.4.2:6501</home>
            </attribute>
            <attribute name="connecthomes">
               <connecthome>10.32.42.2:7500</connecthome>
               <connecthome>192.168.42.2:7501</connecthome>
            </attribute>
            
         </invoker>
         <handlers>
            ...
         </handlers>
      </config>
   </attribute>
</mbean>

Connector connector = new Connector();
         
// Create ServerConfiguration object for socket transport
ServerConfiguration serverConfig = new ServerConfiguration("socket");
            
// Add invokerLocatorParameters (applicable to client and server)
Map locatorConfig = new HashMap();

locatorConfig.put("homes", "10.32.4.2:6500!192.168.4.2:6501");
locatorConfig.put("connecthomes", "10.32.42.2:7500!192.168.42.2:7501");

serverConfig.setInvokerLocatorParameters(locatorConfig);
                   
// Add invocation handlers
...
             
connector.setServerConfiguration(serverConfig);
connector.create();
connector.start();

public interface SocketCreationListener
{
   /**
    * Called when a socket has been created.
    * 
    * @param socket socket that has been created
    * @param source SocketFactory or ServerSocket that created the socket
    * @throws IOException
    */
   void socketCreated(Socket socket, Object source) throws IOException;
}

public InetAddress getAddressSeenByServer() throws Throwable

public Object invoke(InvocationRequest invocation throws Throwable
{
   ...
   InetAddress address = invocation.getRequestPayload().get(Remoting.CLIENT_ADDRESS);
   ...
}

socket://[::1]:3333/?timeout=10000
socket://[::]:4444/?timeout=10000
socket://[::ffff:127.0.0.1]:5555/?timeout=10000
socket://[fe80::205:9aff:fe3c:7800%7]:6666/?timeout=10000
socket://multihome/?homes=[fe80::205:9aff:fe3c:7800%7]:7777![fe80::214:22ff:feef:68bb%4]:8888

InvokerLocator locator = new InvokerLocator("socket://127.0.0.1:5555");
Client client1 = new Client(locator);
Client client2 = new Client(locator);

InvokerLocator locator =
        new InvokerLocator("socket://127.0.0.1:5555/?invokerDestructionDelay=5000");
Client client = new Client(locator);
client.connect();
...
client.disconnect();

The following configuration properties are common to all the current server invokers.

serverBindAddress - The address on which the server binds to listen for requests. The default is an empty value which indicates the server should be bound to the host provided by the locator url, or if this value is null, the local host as provided by InetAddress.getLocalHost() .

serverBindPort - The port to listen for requests on. A value of 0 or less indicates that a free anonymous port should be chosen.

maxNumThreadsOneway - specifies the maximum number of threads to be used within the thread pool for accepting one way invocations on the server side. This property will only be used in the case that the default thread pool is used. If a custom thread pool is set, this property will have no meaning. This property can also be retrieved or set programmatically via the MaxNumberOfOnewayThreads property.

onewayThreadPool - specifies either the fully qualified class name for a class that implements the org.jboss.util.threadpool.ThreadPool interface or the JMX ObjectName for an MBean that implements the org.jboss.util.threadpool.ThreadPool interface. This will replace the default org.jboss.util.threadpool.BasicThreadPool used by the server invoker.

Note that this value will NOT be retrieved until the first one-way (server side) invocation is made. So if the configuration is invalid, will not be detected until this first call is made. The thread pool can also be accessed or set via the OnewayThreadPool property programmatically.

Important to note that the default thread pool used for the one-way invocations on the server side will block the calling thread if all the threads in the pool are in use until one is released.

There are some configurations which will impact the invoker client. These will be communicated to the client invoker via parameters in the Locator URI. These configurations can not be changed during runtime, so can only be set up upon initial configuration of the server invoker on the server side. The following is a list of these and their effects.

clientConnectPort - the port the client will use to connect to the remoting server. This would be needed in the case that the client will be going through a router that forwards requests made externally to a different port internally.

clientConnectAddress - the ip or hostname the client will use to connect to the remoting server. This would be needed in the case that the client will be going through a router that forwards requests made externally to a different ip or host internally.

If no client connect address or server bind address specified, will use the local host's address (via InetAddress.getLocalHost().getHostAddress() ).

Note The role played by "clientConnectAddress" and "clientConnectPort" deserves some further elaboration. When a server is set up, it is either given an InvokerLocator explicitly, or it is given enough information in an MBean XML file or a ServerConfiguration POJO from which to construct an InvokerLocator, and a client uses the host field and port field in the InvokerLocator to determine how to connect to the server. It follows that if an explicit InvokerLocator is passed to the server, then the host and port fields are either given explicitly or are generated, so there is no need for "clientConnectAddress" or "clientConnectPort" fields. However, if the server is configured by way of an MBean XML file or a ServerConfiguration, and no explicit InvokerLocator is specified, then the "clientConnectAddress" and "clientConnectPort" parameters can be used to specify the host and port fields in the InvokerLocator. If they are omitted, then the host and port fields will be derived from the values of the "serverBindAddress" and "serverBindPort" parameters (or generated, if those fields are omitted). Therefore, there is a role for the "clientConnectAddress" and "clientConnectPort" parameters only if clients are meant to connect to a host and port different than the bind host and bind port. Such a situation might occur in the presence of a translating firewall between the client and the server.

If the serverBindAddress property is set, the server invoker will bind to that address. Otherwise, it will, with one exception, use the address in the InvokerLocator (if there is one). The exception is the case in which the clientConnectAddress property is set, which indicates that the adddess in the InvokerLocator is not the real address of the server's host. In that case, and in the case that there is no address in the InvokerLocator, the server will bind to the address of the local host, as determined by the call

InetAddress.getLocalHost().getHostAddress();

In other words, the logic is

if (serverBindAddress is set)
   use it
else if (the host is present in the InvokerLocator and clientConnectAddress is not set)
   use host from InvokerLocator
else
   use local host address

If the serverBindPort property is set, it will be used. If this value is 0 or a negative number, then the next available port will be found and used. If the serverBindPort property is not set, but the clientConnectPort property is set, then the next available port will be found and used. If neither the serverBindPort nor the clientConnectPort is set, then the port specified in the original InvokerLocator will be used. If this is 0 or a negative number, then the next available port will be found and used. In the case that the next available port is used because either the serverBindPort or the original InvokerLocator port value was either 0 or negative, the InvokerLocator will be updated to reflect the new port value.

Note. In the case that a bind port isn't specified, the utility class org.jboss.remoting.transport.PortUtil is used to supply an available port. By default, it will look for a port in the range 1024 to 65535, inclusively. As of release 2.5.2, PortUtil can be configured to search a smaller range by setting the values PortUtil.MIN_PORT (actual value "minPort") and / or PortUtil.MAX_PORT (actual value "maxPort") in the InvokerLocator, a configuration map, an MBean XML file, or a ServerConfiguration object. The range is static; that is, whenever "minPort" or "maxPort" are set, they affect all subsequent calls in the JVM. Note that PortUtil will apply a new "minPort" value only if it is greater than the current value, and it will apply a new "maxPort" value only if it is less than the current value. And it will never apply a new value when the result would be such that the value of "maxPort" would be less than the value of "minPort".

The Socket transport is one of the more complicated invokers mainly because allows the highest degree of configuration. To better understand how changes to configuration properties for the Socket invoker (both client and server) will impact performance and scalability, will discuss the implementation and how it works in detail.

Supports all the configuration attributes as the Socket Invoker. The main difference is that the SSL Socket Invoker uses an SSLServerSocket by default, created by an SSLServerSocketFactory. See section Socket factories and server socket factories for more information.

registryPort - the port on which to create the RMI registry. The default is 3455. This also needs to have the isParam attribute set to true.

Note. The RMI server invoker creates a socket factory and passes it to a client invoker along with the RMI stub, so the socket factory must be serializable. Therefore, if a socket factory is passed in to the server invoker by one of the methods discussed in section Socket factories and server socket factories, then the user is responsible for supplying a serializable socket factory.

Note. Prior to Remoting version 2.4, the RMI transport performed marshalling and unmarshalling only in the client to server direction. As of version 2.4, it will use a marshaller and unmarshaller in the server to client direction, as well. Moreover, marshalling and unmarshalling in the client to server direction has been made more efficient, which results in the transmission of a different sequence of bytes. In case a version 2.4 release of Remoting needs to communicate with an older version, it is possible to request the original marshalling behavior by setting the parameter org.jboss.remoting.transport.rmi.RMIServerInvoker.RMI_ONEWAY_MARSHALLING (actual value "rmiOnewayMarshalling") to "true".

This is essentially identical to the RMI invoker, except that it creates SSL socket and server socket factories by default.

Note. The SSL RMI server invoker creates a socket factory and passes it to a client invoker along with the RMI stub, so the socket factory must be serializable. If the SSL RMI server invoker is allowed to create an SSLSocketFactory from SSL parameters, as discussed in section Socket factories and server socket factories, it will take care to create a serializable socket factory. However, if a socket factory is passed in to the server invoker (also discussed in section Socket factories and server socket factories), then the user is responsible for supplying a serializable socket factory. See sslrmi below for more information.

The HTTP server invoker implementation is based on the Coyote HTTP/1.1 Connector Tomcat component, which is supplied by the JBossWeb implementation in jbossweb.jar.

Note. Prior to release 2.5.0.GA, Remoting also was compatible with the Apache implementation of Tomcat, which is no longer the case. Since JBossWeb requires jdk 1.5 or above, it follows that the HTTP transport in Remoting 2.5.0.GA and above has the same requirement.

The coyote Connector supports GET, POST, HEAD, OPTIONS, and HEAD method types and keep-alive, and most any configuration allowed for Tomcat can be configured for the remoting HTTP server invoker. For more information on the configuration attributes available for the Tomcat connectors, please refer to http://tomcat.apache.org/tomcat-6.0-doc/config/http.html. The Tomcat parameters passed into the http server invoker are passed on to Tomcat. For example, the Tomcat attribute "maxThreads" can be used to set the maximum number of threads to be used to accept incoming http requests. The only exceptions are the Remoting attributes "serverBindAddress" and "serverBindPort", which should be used instead of the Tomcat attributes "address" and "port".

Note. An executor, subclassed from java.util.concurrent.Executor, can be configured and injected into the coyote Connector. As of release 2.5.4.SP2, Remoting can configure and inject an instance of org.apache.catalina.core.StandardThreadExecutor, using attributes passed to Remoting using the key "executor" and a string of the form "attribute0=value0,...,attributeN=valueN". For example, a *-service.xml configuration file could contain

<attribute name="executor">minSpareThreads=20,maxThreads=100</attribute>

Remoting will parse the comma separated list, ignoring white space, create and configure a StandardThreadExecutor, and inject it into the coyote Connector. Note that if an executor is injected, the other threadpool related attributes such as "maxThreads", which would otherwise be applied to a threadpool created by the coyote Connector, are ignored. The configurable attributes of the StandardThreadExecutor are described in http://tomcat.apache.org/tomcat-6.0-doc/config/executor.html.

A feature introduced in Remoting version 2.4 is the ability to configure HTTPClientInvoker to make multiple attempts to complete an invocation. The feature is invoked by setting parameter HTTPClientInvoker.NUMBER_OF_CALL_ATTEMPTS (actual value "numberOfCallAttempts") to the desired integer. The parameter can be configured in the InvokerLocator or in the configuration map passed to the Client. The default value is 1.

Since the remoting HTTP server invoker implementation is using Tomcat connectors, is possible to swap out the Tomcat protocol implementations being used. By default, the protocol being used is org.apache.coyote.http11.Http11Protocol. However, it is possible to switch to use the org.apache.coyote.http11.Http11AprProtocol protocol, which is based on the Apache Portable Runtime (see http://tomcat.apache.org/tomcat-6.0-doc/apr.html for more details). To use the APR implementation, simply put the tcnative-1.dll (or tcnative-1.so) on the system path so it can be loaded. The JBossWeb native libraries, which include tcnative-1.dll/tcnative-1.so, may be downloaded from http://www.jboss.org/jbossweb/.

Client request headers

The HTTP Invoker allows for some of the properties to be passed as request headers from client caller. The following are possible http headers and what they mean:

sessionId - is the remoting session id to identify the client caller. If this is not passed, the HTTP server invoker will try to create a session id based on information that is passed. Note, this means if the sessionId is not passed as part of the header, there is no guarantee that the sessionId supplied to the invocation handler will always indicate the request from the same client.

subsystem - the subsystem to call upon (which invoker handler to call upon). If there is more than one handler per Connector, this will need to be set (otherwise will just use the only one available).

These request headers are set automatically when using a remoting client, but if using another client to send request to the HTTP server invoker, may want to add these headers.

Response headers

If a request on the HTTP transport is made with the org.jboss.remoting.Client method

public Object invoke(Object param, Map metadata) throws Throwable

then org.jboss.remoting.transport.http.HTTPClientInvoker returns the HTTP response headers in a map in metadata, associated with the key org.jboss.remoting.transport.http.HTTPMetadataConstants.RESPONSE_HEADERS (actual value "ResponseHeaders"). For example, the response header "Date" can be retrieved as follows:

Object payload = ... ;
HashMap metadata = new HashMap();
client.invoke(payload, metadata);
Map responseHeaders = (Map) metadata.get(HTTPMetadataConstants.RESPONSE_HEADERS);
String date = (String) responseHeaders.get("Date");

CR/LF in HTTP transport

By default, the HTTP transport uses org.jboss.remoting.marshal.http.HTTPMarshaller and org.jboss.remoting.marshal.http.HTTPUnMarshaller to marshal and unmarshal invocations and responses. Prior to Remoting version 2.4, HTTPUnMarshaller stripped CR/LF characters. As of version 2.4, the default behavior remains the same, but it is possible to change the behavior, on the client and the server, by setting the parameter HTTPUnMarshaller.PRESERVE_LINES (actual value "preserveLines") to "true".

Supports all the configuration attributes as the HTTP Invoker, plus the following:

SSLImplementation - Sets the Tomcat SSLImplementation to use. This should always be org.jboss.remoting.transport.coyote.ssl.RemotingSSLImplementation.

The main difference with the HTTP invoker is that the HTTPS Invoker uses an SSLServerSocket by default, created by an SSLServerSocketFactory. See section Socket factories and server socket factories for more information.

Map metadata = new HashMap();
...

// proxy info
metadata.put("http.proxyHost", "ginger");
metadata.put("http.proxyPort", "80");

...

response = client.invoke(payload, metadata);

-Dhttp.proxyHost=ginger -Dhttp.proxyPort=80 -DproxySet=true

The servlet invoker is a server invoker implementation that uses a servlet running within a web container to accept initial client invocation requests. The servlet request is then passed on to the servlet invoker for processing.

The deployment for this particular server invoker is a little different than the other server invokers since a web deployment is also required. To start, the servlet invoker will need to be configured and deployed. This can be done by adding the Connector MBean service to an existing service xml or creating a new one. The following is an example of how to declare a Connector that uses the servlet invoker:

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Servlet"
       display-name="Servlet transport Connector">

   <attribute name="InvokerLocator">
      servlet://localhost:8080/servlet-invoker/ServerInvokerServlet
   </attribute>

   <attribute name="Configuration">
      <config>
         <handlers>
            <handler subsystem="test">
               org.jboss.test.remoting.transport.web.WebInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
</mbean>

An important point of configuration to note is that the value for the InvokerLocator attribute is the exact url used to access the servlet for the servlet invoker (more on how to define this below), with the exception of the protocol being servlet instead of http. This is important if using automatic discovery, as this is the locator url that will be discovered and used by clients to connect to this server invoker.

The next step is to configure and deploy the servlet that fronts the servlet invoker. The pre-built deployment file for this servlet is the servlet-invoker.war file (which can be found in lib directory of the release distribution or under the output/lib/ directory if doing a source build). By default, it is actually an exploded war, so the servlet-invoker.war is actually a directory so that can be more easily configured (feel free to zip up into an actual war file if prefer). In the WEB-INF directory is located the web.xml file. This is a standard web configuration file and should look like:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC
   "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
   "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>
   <servlet>
      <servlet-name>ServerInvokerServlet</servlet-name>
      <description>
         The ServerInvokerServlet receives requests via HTTP protocol from 
         within a web container and passes it onto the ServletServerInvoker 
         for processing.
      </description>
      <servlet-class>
         org.jboss.remoting.transport.servlet.web.ServerInvokerServlet
      </servlet-class>
      <init-param>
         <param-name>invokerName</param-name>
         <param-value>jboss.remoting:service=invoker,transport=servlet</param-value>
         <description>The servlet server invoker</description>
         <!--
         <param-name>locatorUrl</param-name>
         <param-value>
            servlet://localhost:8080/servlet-invoker/ServerInvokerServlet
         </param-value>
         <description>The servlet server invoker locator url</description>
         -->
      </init-param>
      <load-on-startup>1</load-on-startup>
   </servlet>
   <servlet-mapping>
      <servlet-name>ServerInvokerServlet</servlet-name>
      <url-pattern>/ServerInvokerServlet/*</url-pattern>
   </servlet-mapping>
</web-app>

There are two ways in which the servlet can obtain a reference to the servlet server invoker it needs to pass its request onto. The first is by using the param 'invokerName', as is shown above. The value for this should be the JMX ObjectName for the servlet server invoker that was deployed as a service mbean (see service xml above). The other way is to provide a param 'locatorUrl' with a value that matches the locator url of the servlet server invoker to use. In this case, will use the InvokerRegistry to find the server invoker instead of using JMX, which is useful if not deploying server invoker as a mbean service or if want to run in web container other than the JBoss application server. Note, one or the other param is required. If both are provided, the 'locatorUrl' param take precedence.

This file can be changed to meet any web requirements you might have, such as adding security (see sslservlet) or changing the actual url context that the servlet maps to. If the url that the servlet maps to is changed, will need to change the value for the InvokerLocator in the Connector configuration mentioned above.

Note. Prior to Remoting version 2.4, org.jboss.remoting.transport.servlet.ServletServerInvoker generated a single MBean ObjectName for representing ServletServerInvokers as MBeans, which meant that an MBeanServer could be aware of only a single ServletServerInvoker MBean. As of version 2.4, that restriction has been eliminated.

Note. Prior to Remoting version 2.4, when org.jboss.remoting.transport.servlet.web.ServerInvokerServlet retrieved an MBeanServer, it looked only for an MBeanServer whose default domain was "jboss". As of version 2.4, the default domain can be configured by adding an "mbeanServer" init-param element to the web.xml file. If the "mbeanServer" value is set to "*platform*" and jdk 1.5 or greater is in use, ServerInvokerServlet will retrieve the platform MBeanServer by calling java.lang.management.ManagementFactory.getPlatformMBeanServer(). In the absence of a configured default domain, ServerInvokerServlet will still use "jboss" as the default domain.

The SSL Servlet Invoker is exactly the same as its parent, Servlet Invoker, with the exception that it uses the protocol of 'sslservlet'. On the server side it is deployed exactly the same as a servlet invoker would be but requires setting up ssl within the web container (i.e. enabling the ssl connector within Tomcat's server.xml). This will usually require specifing a different port as well.

An example of the mbean service xml for deploying the ssl servlet server invoker would be:

<?xml version="1.0" encoding="UTF-8"?>
<server>
   <mbean code="org.jboss.remoting.transport.Connector"
          name="jboss.remoting:service=Connector,transport=SSLServlet"
          display-name="SSL Servlet transport Connector">

      <attribute name="InvokerLocator">
         sslservlet://localhost:8443/servlet-invoker/ServerInvokerServlet
      </attribute>
      <attribute name="Configuration">
         <config>
            <handlers>
               <handler subsystem="test">
                  org.jboss.test.remoting.transport.web.WebInvocationHandler
               </handler>
            </handlers>
         </config>
      </attribute>
   </mbean>
</server>

An example of servlet-invoker.war/WEB-INF/web.xml for the ssl server invoker servlet would be:

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE web-app PUBLIC
    "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
    "http://java.sun.com/dtd/web-app_2_3.dtd">

<web-app>
   <servlet>
      <servlet-name>ServerInvokerServlet</servlet-name>
      <description>
         The ServerInvokerServlet receives requests via HTTP protocol from 
         within a web container and passes it onto the ServletServerInvoker
         for processing.
      </description>
      <servlet-class>
         org.jboss.remoting.transport.servlet.web.ServerInvokerServlet
      </servlet-class>
      <init-param>
         <param-name>locatorUrl</param-name>
         <param-value>
            sslservlet://localhost:8443/servlet-invoker/ServerInvokerServlet
         </param-value>
         <description>The servlet server invoker locator url</description>
      </init-param>
      <load-on-startup>1</load-on-startup>
   </servlet>
   <servlet-mapping>
      <servlet-name>ServerInvokerServlet</servlet-name>
      <url-pattern>/ServerInvokerServlet/*</url-pattern>
   </servlet-mapping>
</web-app>

Web based clients, meaning remoting clients that call on web based remoting servers (i.e. http, https, servlet, and sslservlet) have special needs when it comes to handling exceptions that come from the servers they are calling on. The main reason for this is that depending on what type of server they are calling on, they might receive the error in different formats.

By default, web based clients will throw an exception when the response code from the server is greater than 400. The exact exception type thrown will depend on the type of web server the client is interacting with. If it is a JBoss Remoting server (http or https server invoker), the exception thrown will be the one originally generated on the server side. If the server is not a JBoss Remoting server (e.g. JBossAS, Tomcat, Apache Web Server, etc.), the exception thrown will be org.jboss.test.remoting.transport.http.WebServerError. The WebServerError's message will be the error html returned by the web server. Throwing an exception may be turned off with the parameter HTTPMetadataConstants.NO_THROW_ON_ERROR (actual text value "NoThrowOnError") set to "true". This parameter may be passed in the InvokerLocator or configuration map when the org.jboss.remoting.Client is created, or it may be included in the metadata map passed to

public Object invoke(Object param, Map metadata) throws Throwable;

This will cause the http client invoker to not throw an exception, but instead return the data from the web server error stream. In the case that the data returned from this error stream is of type java.lang.String (i.e. is error html), it will be wrapped in a WebServerError and returned as this type. The raw data from the web server can the be retrieved by getting the WebServerError's message.

Note. Prior to Remoting version 2.4, the servlet transport returned a simple error message in the event of an error on the server side. As of version 2.4, the discussion about exception handling applies to the servlet and sslservlet transports as well. The original behavior of returning an error message can be requested by configuring the server with the parameter org.jboss.remoting.transport.http.HTTPMetadataConstants.DONT_RETURN_EXCEPTION (actual value "dont-return-exception") set to "true".

As of Remoting version 2.4, the multiplex transport is deprecated and will no longer be supported.

As of Remoting version 2.4, the sslmultiplex transport is deprecated and will no longer be supported.

The bisocket transport, like the multiplex transport, is a bidirectional transport that can function in the presence of restrictions that would prevent a unidirectional transport like socket or http from creating a server to client push callback connection. (See Section Callbacks for more information about callbacks and bidirectional and unidirectional transports.) For example, security restrictions could prevent the application from opening a ServerSocket on the client, or firewall restrictions could prevent the server from contacting a ServerSocket even if it were possible to create one.

5.4.16.2. Details

Using the bisocket transport certainly does not require understanding its implementation details, but some further information is presented in this section for those who might be interested.

In the following discussion, the client side client invoker and the server side server invoker will be referred to simply as "client invoker" and "server invoker." The callback client invoker and callback server invoker will be explicitly identified as such.

The following sequence of events occurs in the course of creating a control connection. For simplicity it is assumed that the Client and Connector have already been created, and that the callback server is created implicitly by the Client. These events are illustrated in Figure 5.1.

1. The application calls Client.addListener().
2. The Client creates a callback Connector and the callback server invoker registers itself in a static map.
3. The Client sends an "addListener" message to the server invoker by way of the client invoker.
4. The client invoker intercepts the "addListener" message, which tells it that a callback server is being created. It retrieves the callback server invoker from the static map and tells it to create a control connection for the callback connection that is being constructed.
5. The callback server invoker sends an internal message to the server invoker requesting the address and port of the secondary ServerSocket
6. The callback server invoker connects to the secondary ServerSocket to create a Socket for the control connection. If it has not already done so, the callback server invoker creates a TimerTask which will monitor the state of all of its control connections. (Note that if the callback Connector is created explicitly, it could have multiple InvokerCallbackHandlers registered with it.)
7. On the server side, the Socket just created by the secondary ServerSocket is stored in a static map, awaiting the creation of the callback client invoker.
8. The client invoker transmits the "addListener" message to the server invoker.
9. The server invoker creates a callback client invoker.
10. The callback client invoker retrieves the waiting socket and uses it for the control connection.
11. The callback client invoker begins pinging on the control connection.

Figure 5.1. Creating a control connection.

The following sequence of events occurs in the course of creating a connection for the callback client invoker to use for sending callbacks. It is illustrated in Figure 5.2.

1. The ServerInvocationHandler calls InvokerCallbackHandler.handleCallback().
2. The InvocationCallbackHandler calls invoke() on the callback Client.
3. The Client calls invoke() on the callback client invoker.
4. If there are no connections in its connection pool, the callback client invoker sends a message on the control connection asking the callback server invoker to connect to the server side secondary ServerSocket. It then waits for the Socket to appear in a static map.
5. The callback server invoker receives the request and calls upon either a Socket constructor or a SocketFactory to create a new Socket. It passes the new Socket to a worker thread to process subsequent callback invocations.
6. The secondary ServerSocket creates a new Socket, which is placed in a static map.
7. The callback client invoker retrieves the new Socket
8. The callback client uses the new Socket to transmit a callback, and adds the new connection to its connection pool for later use.

Figure 5.2. Creating a callback connection.

The following sequence of events occurs when a control connection fails. It is illustrated in Figure 5.3.

1. The callback server invoker notices that a ping has not been received during the control connection's current window.
2. The callback server invoker reacquires the host and port of the secondary ServerSocket, just in case it has changed.
3. The callback server invoker calls on a Socket constructor or SocketFactory to create a new Socket.
4. The callback server invoker sends an internal message on the new connection directing the server to replace the current control connection with the new connection.
5. After the secondary ServerSocket creates a new Socket, the Socket is passed directly to the client invoker in a method that replaces the old control connection with a new one.

Figure 5.3. Replacing a failed control connection.

The SSL bisocket transport has the same relation to the bisocket transport as the SSL socket transport has to the socket transport. That is, it uses an SSLServerSocket and creates SSLSockets by default. See Section Socket factories and server socket factories for more information.

SSL bisocket transport supports all the configuration attributes supported by the bisocket transport.

Although this section covers callback configuration, it will be useful to begin with a little general information about callbacks within Remoting. In addition to the ordinary remote method invocation model, in which invocation results are returned synchronously, Remoting also supports an invocation model in which the server asynchronously generates information to be returned to the client.

There are two models for callbacks, push callbacks and pull callbacks. In the push model, the client registers a client side callback server with the target server. When the target server has a callback to deliver, it will call on the callback server directly and send the callback message. The other model, pull callbacks, allows the client to call on the target server to collect the callback messages waiting for it.

public void addListener(InvokerCallbackHandler callbackHandler);

public void handleCallback(Callback callback) throws HandleCallbackException;

public void handleCallbackOneway(Callback callback) throws HandleCallbackException;
  
public void handleCallbackOneway(Callback callback, boolean serverSide)
        throws HandleCallbackException;

public void invokeOneway(Object param, Map sendPayload, boolean clientSide) throws Throwable;

public interface CallbackListener
{
   /**
    * @param callbackHandler InvokerCallbackHandler that handled this callback
    * @param callbackId id of callback being acknowledged
    * @param response either (1) response sent with acknowledgement or (2) null
    */
   void acknowledgeCallback(
           InvokerCallbackHandler callbackHandler, Object callbackId, Object response);
}

public int acknowledgeCallback(
        InvokerCallbackHandler callbackHandler, Callback callback) throws Throwable;
           
public int acknowledgeCallback(
        InvokerCallbackHandler callbackHandler, Callback callback, Object response) throws Throwable;
           
public int acknowledgeCallbacks(
        InvokerCallbackHandler callbackHandler, List callbacks) throws Throwable;
           
public int acknowledgeCallbacks(
        InvokerCallbackHandler callbackHandler, List callbacks, List responses) throws Throwable;

There are several ways in which callback handlers can be configured. The main distinction in type of callback setup is whether the callbacks will be push (asynchronous) or pull (synchronous) callbacks.

public void addListener(
        InvokerCallbackHandler) throws Throwable;
          
public void addListener(
        InvokerCallbackHandler callbackHandler, InvokerLocator clientLocator) throws Throwable;
          
public void addListener(
        InvokerCallbackHandler callbackHandler,  InvokerLocator clientLocator,
        Object callbackHandlerObject) throws Throwable;

public List getCallbacks(InvokerCallbackHandler callbackHandler) throws Throwable

public List getCallbacks(
        InvokerCallbackHandler callbackHandler, Map metadata) throws Throwable;

public void addListener(
        InvokerCallbackHandler callbackHandler, InvokerLocator clientLocator) throws Throwable;
          
public void addListener(
        InvokerCallbackHandler callbackHandler,InvokerLocator clientLocator,
        Object callbackHandlerObject) throws Throwable;

public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata) throws Throwable;
          
public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata,
        Object callbackHandlerObject) throws Throwable;
          
public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata,
        Object callbackHandlerObject, boolean serverToClient) throws Throwable;

InvokerCallbackHandler callbackHandler = new SampleCallbackHandler();
client.addListener(callbackHandler, new HashMap(), null, true);
client.addListener(callbackHandler, new HashMap(), null, true);

public Set getCallbackConnectors(InvokerCallbackHandler callbackHandler);

InvokerCallbackHandler callbackHandler1 = new SampleCallbackHandler();
client.addListener(callbackHandler1, new HashMap(), null, true);
Set callbackConnectors = client.getCallbackConnectors(callbackHandler1);
Connector callbackConnector = (Connector) callbackConnectors.iterator().next();
InvokerCallbackHandler callbackHandler2 = new SampleCallbackHandler();
client.addListener(callbackHandler2, callbackConnector.getLocator());

InvokerCallbackHandler callbackHandler1 = new SampleCallbackHandler();
client.addListener(callbackHandler1, new HashMap(), null, true);
Set callbackConnectors = client.getCallbackConnectors(callbackHandler1);
Connector callbackConnector = (Connector) callbackConnectors.iterator().next();
client.addListener(callbackHandler1, callbackConnector.getLocator());

Callback connections are torn down through a call to the method

public void removeListener(InvokerCallbackHandler callbackHandler) throws Throwable;

in the org.jboss.remoting.Client class. A Client can unregister only those InvokerCallbackHandlers that it originally registered.

It is good practice to eliminate callback connections when they are no longer needed. For example, callback Connectors can, depending on the transport, occupy TCP ports, and CallbackPollers will continue to poll as long as a connection exists.

All callback store configuration will need to be defined within the server invoker configuration, since the server invoker is the parent that creates the callback stores as needed (when client registers for pull callbacks). Example service xml files are included below.

The following general callback store parameters may be configured. They are defined as constants in the org.jboss.callback.ServerInvokerCallbackHandler class.

CALLBACK_MEM_CEILING (actual value is "callbackMemCeiling"): the percentage of free memory available before callbacks will be persisted. If the memory heap allocated has reached its maximum value and the percent of free memory available is less than the callbackMemCeiling, this will trigger persisting of the callback message. The default value is 20.

Note: The calculations for this is not always accurate. The reason is that total memory used is usually less than the max allowed. Thus, the amount of free memory is relative to the total amount allocated at that point in time. It is not until the total amount of memory allocated is equal to the max it will be allowed to allocate. At this point, the amount of free memory becomes relevant. Therefore, if the memory percentage ceiling is high, it might not trigger until after free memory percentage is well below the ceiling.

CALLBACK_STORE_KEY (actual value is "callbackStore"): specifies the callback store to be used. The value can be either an MBean ObjectName or a fully qualified class name. If using class name, the callback store implementation must have a void constructor. The default is to use the NullCallbackStore.

The following parameters specific to CallbackStore can be configured via the invoker configuration as well. They are defined as constants in the CallbackStore class.

FILE_PATH_KEY (actual value is "StoreFilePath"): indicates to which directory to write the callback objects. The default value is the property value of 'jboss.server.data.dir' and if this is not set, then will be 'data'. Will then append 'remoting' and the callback client's session id. An example would be 'data\remoting\5c4o05l-9jijyx-e5b6xyph-1-e5b6xyph-2'.

FILE_SUFFIX_KEY (actual value is "StoreFileSuffix"): indicates the file suffix to use for the callback objects written to disk. The default value is 'ser'.

Sample service configuration

Socket transport with callback store specified by class name and memory ceiling set to 30%:

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">

   <attribute name="Configuration">
      <config>
         <invoker transport="socket">
            <attribute name="callbackStore">
               org.jboss.remoting.callback.CallbackStore
            </attribute>
            <attribute name="callbackMemCeiling">30</attribute>
         </invoker>
         <handlers>
            <handler subsystem="test">
               org.jboss.remoting.callback.pull.memory.CallbackInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
</mbean>

Socket transport with callback store specified by MBean ObjectName and declaration of CallbackStore as service:

<mbean code="org.jboss.remoting.callback.CallbackStore"
       name="jboss.remoting:service=CallbackStore,type=Serializable"
       display-name="Persisted Callback Store">

   <!-- the directory to store the persisted callbacks into -->
   <attribute name="StoreFilePath">callback_store</attribute>
   <!-- the file suffix to use for each callback persisted to disk -->
   <attribute name="StoreFileSuffix">cbk</attribute>
</mbean>

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">

   <attribute name="Configuration">
      <config>
         <invoker transport="socket">
            <attribute name="callbackStore">
               jboss.remoting:service=CallbackStore,type=Serializable
            </attribute>
         </invoker>
         <handlers>
            <handler subsystem="test">
               org.jboss.remoting.callback.pull.memory.CallbackInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
</mbean>

Socket transport with callback store specified by class name and the callback store's file path and file suffix defined:

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">

   <attribute name="Configuration">
      <config>
         <invoker transport="socket">
            <attribute name="callbackStore">
               org.jboss.remoting.callback.CallbackStore
            </attribute>
            <attribute name="StoreFilePath">callback</attribute>
            <attribute name="StoreFileSuffix">cst</attribute>
         </invoker>
         <handlers>
            <handler subsystem="test">
               org.jboss.remoting.callback.pull.memory.CallbackInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
</mbean>

Since performing callbacks can sometimes fail, due to network errors or errors produced by the client callback handler, there needs to be a mechanism for managing exceptions when delivering callbacks. This is handled via use of the org.jboss.remoting.callback.CallbackErrorHandler interface. Implementations of this interface can be registered with the Connector to control the behavior when callback exceptions occur.

The implementation of the CallbackErrorHandler interface can be specified by setting the 'callbackErrorHandler' attribute to either the ObjectName of an MBean instance of the CallbackErrorHandler which is already running and registered with the MBeanServer, or can just specify the fully qualified class name of the CallbackErrorHandler implementation (which will be constructed on the fly and must have a void parameter constructor). The full server invoker configuration will be passed along to the CallbackErrorHandler, so if want to add extra configuration information in the invoker's configuration for the callback error handler, it will be available. If no callback error handler is specified via configuration, org.jboss.remoting.callback.DefaultCallbackErrorHandler will be used by default. This implementation will allow up to 5 exceptions to occur when trying to deliver a callback message from the server to the registered callback listener client (regardless of what the cause of the exception is, so could be because could not connect or could be because the client actually threw a valid exception). After the DefaultCallbackErrorHandler receives its fifth exception, it will remove the callback listener from the server invoker handler and shut down the callback listener proxy on the server side. The number of exceptions the DefaultCallbackErrorHandler will allow before removing the listener can by configured by the 'callbackErrorsAllowed' attribute.

Note. As of Remoting version 2.4, an org.jboss.remoting.callback.ServerInvokerCallbackHandler, which manages both push and pull callbacks on the server side, can register to be informed of a failure on the connection to the client that it is servicing. In particular, if there is a lease registered for the connection for that particular client, then the ServerInvokerCallbackHandler can be registered as a org.jboss.remoting.ConnectionListener for that lease. The default behavior is to do the registration, but the parameter org.jboss.remoting.ServerInvoker.REGISTER_CALLBACK_LISTENER (actual value "registerCallbackListener") may be set to "false" to prevent registration. If leasing is enabled and registration is turned on, a ServerInvokerCallbackHandler will shut itself down upon being informed of a connection failure. For more information about leasing, see Network Connection Monitoring.

All server invokers use server sockets, and it makes sense, therefore, to be able to configure server invokers with server socket factories. It is also true, though less obvious. that server invokers create sockets (other than by way of server sockets). When a server invoker makes a push callback to a client, it creates a client invoker, which creates a socket. Moreover, some server invokers, e.g., the RMI server invoker, have their own idiosyncratic uses for socket factories. Remoting offers a number of ways of configuring socket factories and server socket factories, and these apply to all transports (except for the servlet invokers).

On the client side it is possible to configure socket factories for client invokers and to configure server socket factories for callback server invokers. Configuration on the client side is largely the same as configuration on the server side, with the exception that no MBeanServer is assumed to be present, and the Client has no facilities for parsing xml documents.

Everything in the previous two sections applies to configuring socket and server socket factories in any environment, including inside the JBoss Application Server (JBossAS), but JBossAS adds some new options. In particular, the SARDeployer (see The JBoss 4 Application Server Guide on the labs.jboss.org web site) can read information from a *-service.xml file, as discussed above in the section "General Connector and Invoker configuration," and use it to configure MBeans such as Connectors.

An example of a service xml that covers all the different transport and service configurations can be found within the example-service.xml file under the etc directory of the JBoss Remoting distribution.

The server socket factory to be used by a server invoker can be set via configuration within the service xml. To do this, the serverSocketFactory attribute will need to be set as a sub-element of the invoker element (this cannot be done if just specifying the invoker configuration using the InvokerLocator attribute). The attribute value must be either

An example of the first case would be:

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=Socket"
       display-name="Socket transport Connector">

   <attribute name="Configuration">
      <config>
         <invoker transport="sslsocket">
            <attribute name="serverSocketFactory">
               jboss.remoting:service=ServerSocketFactory,type=SSL
            </attribute>
            <attribute name="numAcceptThreads">1</attribute>
            ...

The serverSocketFactory attribute is processed as follows:

The JBossRemoting project provides an implementation of the ServerSocketFactoryMBean that can be used and should provide most of the customization features that would be needed. More on this implementation later.

Note that these two options correspond exactly to options 4 and 5 in section Server socket factories (on the server side), which is how these two new options are implemented.

Timing considerations. If a Connector is accessed by way of the MBeanServer, then most of the options for configuring the server socket factory discussed in Server socket factories are irrelevant since ConnectorMBean does not expose methods for using them. However, when a Connector that is registered with an MBeanServer creates a server invoker during a call to Connector.create(), it also registers the server invoker with the same MBeanServer, which means that the server invoker is accessible by way of its ObjectName, which has the form

jboss.remoting:service=invoker,transport=socket,host=www.jboss.com,port=8765

for example, followed by additional parameter=value pairs. (See the jmx-console for a running instance of JBossAS at http://localhost:8080/jmx-console/ to see examples of server invoker ObjectNames.) Now, if another MBean is configured in a *-service.xml file to be dependent on the server invoker MBean, e.g.

<mbean code="org.jboss.BlueMonkey" name="jboss.remoting:bluemonkey,name=diamond">
   <depends optional-attribute-name="serverInvoker">
      jboss.remoting:service=invoker,transport=socket,host=www.jboss.com,port=8765
   </depends>
</mbean>

then org.jboss.BlueMonkey.create() will have access to the designated server invoker after the invoker has been created but before it has been started, which means that ServerInvoker.setServerSocketFactory() will be effective. (See the The JBoss 4 Application Server Guide, Chapter 2, for more information about the life cycle of JBoss MBeans.)

As described in sections Declarative configuration: MBeans and Declarative configuration: POJOs, the declarative xml files used by the Application Server can be used to configure the client by way of the parameters included in the InvokerLocator. However, a peculiarity in the way socket factories are created on the client restricts the parameters taken into consideration to those passed in the configuration map passed to the org.jboss.remoting.Client constructor. The following two parameters, introduced in releases 2.4.0.SP1 and 2.5.2, respectively, eliminate that restriction.

org.jboss.remoting.Remoting.SOCKET_FACTORY_NAME (actual value is 'socketFactory') - key for giving the name of the socket factory class to be used by clients.

org.jboss.remoting.Remoting.USE_ALL_SOCKET_FACTORY_PARAMS (actual value is 'useAllSocketFactoryParams') - key for indicating that all socket factory parameters in the InvokerLocator should be used by clients.

Note that the parameter org.jboss.remoting.Remoting.CONFIG_OVERRIDES_LOCATOR (actual value "configOverridesLocator"), described in section org.jboss.remoting.Remoting, is also relevant.

Every Remoting transport uses Sockets, but the creation and management of the Sockets is generally inaccessible from the application code. Remoting has a hook that can provide access to Sockets, in the form of a listener interface in the org.jboss.remoting.socketfactory package:

public interface SocketCreationListener
{
   /**
    * Called when a socket has been created.
    * 
    * @param socket socket that has been created
    * @param source SocketFactory or ServerSocket that created the socket
    * @throws IOException
    */
   void socketCreated(Socket socket, Object source) throws IOException;
}

Socket creation listeners can be registered to be informed every time a socket is created by a SocketFactory or ServerSocket. The mechanisms for registering listeners are the usual ones, e.g., by putting them in configuration maps passed to client and server invokers. (See Section General transport configuration for a general discussion of parameter configuration in Remoting.) In any case they should be associated with one of the following keys from org.jboss.remoting.Remoting:

/**
 * Key for the configuration map passed to a Client or Connector to indicate
 * a socket creation listener for sockets created by a SocketFactory.
 */
public static final String SOCKET_CREATION_CLIENT_LISTENER = "socketCreationClientListener";
      
/**
 * Key for the configuration map passed to a Client or Connector to indicate
 * a socket creation listener for sockets created by a ServerSocket.
 */
public static final String SOCKET_CREATION_SERVER_LISTENER = "socketCreationServerListener";

The value associated with either of these keys can be an actual object, or, to facilitate configuration by InvokerLocator or xml, it can be the name of a class that implements SocketCreationListener and has a default constructor

Note that client and server invokers always use the respective keys SOCKET_CREATION_CLIENT_LISTENER and SOCKET_CREATION_SERVER_LISTENER, whether they are on the client side or server side. For example, a callback client invoker would be configured by putting a listener with the key SOCKET_CREATION_CLIENT_LISTENER in the configuration map passed to the server side Connector, which will find its way to the callback client invoker when a callback handler is registered.

The creation listener facility currently is supported by the following transports: bisocket, sslbisocket, https, rmi, sslrmi, socket, and sslsocket. It is not supported by http because HttpURLConnection does not expose its socket factory (though HttpsURLConnection does). It is not supported by the servlet transport because invocations with the servlet transport go through a servlet container, which is outside the scope of Remoting.

There are now four transports that support SSL: https, sslrmi, and sslsocket (plus sslservlet, which is not relevant here). All of the preceding discussion applies to each of these, and, moreover, they are all extensions of their non-ssl counterparts, so only some ssl specific information will be added here.

https

Configuration of the https transport is a bit different from that of the other transports since the implementation is based off the Tomcat connectors. One difference is that, in order to use SSL connections, the SSLImplementation attribute must be set and must always have the value org.jboss.remoting.transport.coyote.ssl.RemotingSSLImplementation. The SSLImplementation is used by the Tomcat connector to create ServerSocketFactorys, and RemotingSSLImplementation presents Tomcat with the ServerSocketFactory configured according to the options described above.

An example of setting up https via service.xml configuration would be:

<mbean code="org.jboss.remoting.transport.Connector"
       name="jboss.remoting:service=Connector,transport=HTTPS"
       display-name="HTTPS transport Connector">

   <attribute name="Configuration">
      <config>
         <invoker transport="https">
            <attribute name="serverSocketFactory">
               jboss.remoting:service=ServerSocketFactory,type=SSL
            </attribute>
            <attribute name="SSLImplementation">
               org.jboss.remoting.transport.coyote.ssl.RemotingSSLImplementation
            </attribute>
            <attribute name="serverBindAddress">${jboss.bind.address}</attribute>
            <attribute name="serverBindPort">6669</attribute>
         </invoker>
         <handlers>
            <handler subsystem="mock">
               org.jboss.test.remoting.transport.mock.MockServerInvocationHandler
            </handler>
         </handlers>
      </config>
   </attribute>
   <!-- This depends is included because need to make sure
        this mbean is running before configure invoker. -->
   <depends>jboss.remoting:service=ServerSocketFactory,type=SSL</depends>
</mbean>

See section SSLServerSocketFactoryService below for a discussion of the "jboss.remoting:service=ServerSocketFactory,type=SSL" MBean that appears in this configuration element.

Note that the configuration for SSL support only works when using the java based http processor and not with the APR based transport. See section HTTP Invoker for more information on using the APR based transport.

sslrmi

The extra twist in the sslrmi invoker is that the server invoker creates the (client) socket factory and packages it with its own stub, from which it follows that the socket factory must be serializable. If the sslrmi server invoker is allowed to create an SSLSocketFactory from SSL parameters, it will take care to create a serializable socket factory. In particular, the server invoker creates a copy of org.jboss.remoting.transport.rmi.ssl.SerializableSSLClientSocketFactory, which is essentially just a holder for the configuration map passed to the server invoker, with any parameters removed which concern trust store and key store configuration. On the client side, when an sslrmi client invoker is created, it stores its own configuration map in a static variable which the transferred SerializableSSLClientSocketFactory can retrieve and merge with the configuration information it brought with it from the server. In particular, if a socket factory is explicitly passed to the client invoker, then SerializableSSLClientSocketFactory will use it. If not, then SerializableSSLClientSocketFactory will use any key store and trust store information passed to the client to create and configure a socket factory.

Note. If instead of using SerializableSSLClientSocketFactory, a socket factory is passed in to the server invoker by one of the methods discussed above, then the user is responsible for supplying a serializable socket factory.

sslsocket

In addition to the various configuration options discussed above, the sslsocket transport exposes the

public void setServerSocketFactory(ServerSocketFactory serverSocketFactory)

method as a JMX operation.

Also, the sslsocket server invoker inherits from the socket server invoker a method with signature

public void setNewServerSocketFactory(ServerSocketFactory serverSocketFactory)

which supports dynamic replacement of server socket factories. The principal motivation for this facility is to be able to swap in a new SSLServerSocketFactory configured with an updated keystore.

Throughout this section reference has been made to SSL socket factory and server socket factory configuration parameters. This subsection will introduce these parameters in the context of configuring org.jboss.remoting.security.SSLSocketBuilder, Remoting's flexible, highly customizable master factory for creating socket and server socket factories. It can be used programmatically on both the client and server side, and it is also a service MBean, so it can be configured and started from within a service xml in a JBossAS environment.

Once a SSLSocketBuilder has been constructed and configured, a call to its method createSSLServerSocketFactory() will return a custom instance of a SSLServerSocketFactory, and a call to createSSLSocketFactory() will return a custom instance of SSLSocketFactory.

There are two modes in which the SSLSocketBuilder can be run. The first is the default mode where all that is needed is to declare the SSLSocketBuilder and set the system properties javax.net.ssl.keyStore and javax.net.ssl.keyStorePassword. This will use the JVM vendor's default configuration for creating the SSL server socket factory.

In order to customize any of the SSL properties, the first requirement is that the default mode is turned off. This is IMPORTANT because otherwise, if the default mode is not explicitly turned off, all other settings will be IGNORED, even if they are explicitly set. To turn off the default mode via service xml configuration, set the UseSSLServerSocketFactory attribute to false. This can also be done programmatically by calling the setUseSSLServerSocketFactory() and passing false as the parameter value.

There are two ways to configure a SSLSocketBuilder

The configuration properties for SSLSocketBuilderare as follows. Note that in the "key name" column, the name in capital letters (e.g., REMOTING_CLIENT_AUTH_MODE) is a handy constant in the SSLSocketBuilder class with the value given in parentheses (e.g. "org.jboss.remoting.clientAuthMode"). It is the latter that should be used for declarative configuration in, for example, MBean descriptors.

Note. If any of the attributes KeyStoreURL, KeyStorePassword, KeyStoreType, TrustStoreURL, TrustStorePassword, or TrustStoreType are left unconfigured, SSLSocketBuilder will also examine the corresponding standard SSL system properties "javax.net.ssl.keyStore", "javax.net.ssl.keyStorePassword", "javax.net.ssl.keyStoreType", "javax.net.ssl.trustStore", "javax.net.ssl.trustStorePassword", "javax.net.ssl.trustStoreType". In the cases of KeyStoreType and TrustStoreType, SSLSocketBuilder will then go on to use default values after checking the system properties.

The following is an example of configuring a SSLSocketBuilder and using it to create a custom SSLSocketFactory:

protected SSLSocketFactory getSocketFactory() throws Exception
{
   HashMap config = new HashMap();
   config.put(SSLSocketBuilder.REMOTING_KEY_STORE_TYPE, "JKS");
   String keyStoreFilePath = getKeystoreFilePath();
   config.put(SSLSocketBuilder.REMOTING_KEY_STORE_FILE_PATH, keyStoreFilePath);
   config.put(SSLSocketBuilder.REMOTING_KEY_STORE_PASSWORD, "unit-tests-server");
   config.put(SSLSocketBuilder.REMOTING_SSL_PROTOCOL, "SSL");
   SSLSocketBuilder builder = new SSLSocketBuilder(config);
   builder.setUseSSLSocketFactory(false);
   return builder.createSSLSocketFactory();
}

More examples of configuring SSLSocketBuilder can be found in the class FactoryConfigSSLSample in the package org.jboss.remoting.samples.config.factories.

The following is an example of configuring SSLSocketBuilder in a *-service.xml file:

<!-- This service is used to build the SSL Server socket factory -->
<!-- This will be where all the store/trust information will be set. -->
<!-- If do not need to make any custom configurations, no extra attributes -->
<!-- need to be set for the SSLSocketBuilder and just need to set the -->
<!-- javax.net.ssl.keyStore and javax.net.ssl.keyStorePassword system properties. -->
<!-- This can be done by just adding something like the following to the run -->
<!-- script for JBoss -->
<!-- (this one is for run.bat): -->
<!-- set JAVA_OPTS=-Djavax.net.ssl.keyStore=.keystore -->
<!-- -Djavax.net.ssl.keyStorePassword=opensource %JAVA_OPTS% -->
<!-- Otherwise, if want to customize the attributes for SSLSocketBuilder, -->
<!-- will need to uncomment them below. -->
<mbean code="org.jboss.remoting.security.SSLSocketBuilder"
       name="jboss.remoting:service=SocketBuilder,type=SSL"
       display-name="SSL Server Socket Factory Builder">
   <!-- IMPORTANT - If making ANY customizations, this MUST be set to false. -->
   <!-- Otherwise, will used default settings and the following attributes will be ignored. -->
   <attribute name="UseSSLServerSocketFactory">false</attribute>
   <!-- This is the url string to the key store to use -->
   <attribute name="KeyStoreURL">.keystore</attribute>
   <!-- The password for the key store -->
   <attribute name="KeyStorePassword">opensource</attribute>
   <!-- The password for the keys (will use KeystorePassword if this is not set explicitly. -->
   <attribute name="KeyPassword">opensource</attribute>
   <!-- The protocol for the SSLContext. Default is TLS. -->
   <attribute name="SecureSocketProtocol">TLS</attribute>
   <!-- The algorithm for the key manager factory. Default is SunX509. -->
   <attribute name="KeyManagementAlgorithm">SunX509</attribute>
   <!-- The type to be used for the key store. -->
   <!-- Defaults to JKS. Some acceptable values are JKS (Java Keystore - Sun's keystore format), -->
   <!-- JCEKS (Java Cryptography Extension keystore - More secure version of JKS), and -->
   <!-- PKCS12 (Public-Key Cryptography Standards #12 keystore - RSA's Personal Information Exchange Syntax Standard). -->
   <!-- These are not case sensitive. -->
   <attribute name="KeyStoreType">JKS</attribute>
</mbean>

It is also possible to set the default socket factory to be used when not using customized settings (meaning UseSSLSocketFactory property value is true, which is the default). This can be done by setting system property of org.jboss.remoting.defaultSocketFactory to the fully qualified class name of the javax.net.SocketFactory implementation to use. Will then call the getDefault() method on that implementation to get the SocketFactory instance to use.

Although any server socket factory can be set for the various transports, there is a customizable server socket factory service provided within JBossRemoting that supports SSL. This is the org.jboss.remoting.security.SSLServerSocketFactoryService class. The SSLServerSocketFactoryService class extends the javax.net.ServerSocketFactory class and also implements the SSLServerSocketFactoryServiceMBean interface (so that it can be set using the socketServerFactory attribute described previously). Other than providing the proper interfaces, this class is a simple wrapper around the org.jboss.remoting.security.SSLSocketBuilder class.

The following is an example of configuring SSLServerSocketFactoryService in a *-service.xml file. Note that it depends on the SSLSocketBuilder MBean defined in the xml fragment above:

<!-- This service provides the exact same API as the ServerSocketFactory, so -->
<!-- can be set as an attribute of that type on any MBean requiring an ServerSocketFactory. -->
<mbean code="org.jboss.remoting.security.SSLServerSocketFactoryService"
       name="jboss.remoting:service=ServerSocketFactory,type=SSL"
       display-name="SSL Server Socket Factory">
   <depends optional-attribute-name="SSLSocketBuilder"
            proxy-type="attribute">jboss.remoting:service=SocketBuilder,type=SSL</depends>
</mbean>

Since we are talking about keystores and truststores, this section will quickly go over how to quickly generate a test keystore and truststore for testing. This is not intended to be a full security overview, just an example of how I originally created mine for testing.

To get started, will need to create key store and trust store.

Generating key entry into keystore:

C:\tmp\ssl>keytool -genkey -alias remoting -keyalg RSA
Enter keystore password: opensource
What is your first and last name?
[Unknown]: Tom Elrod
What is the name of your organizational unit?
[Unknown]: Development
What is the name of your organization?
[Unknown]: JBoss Inc
What is the name of your City or Locality?
[Unknown]: Atlanta
What is the name of your State or Province?
[Unknown]: GA
What is the two-letter country code for this unit?
[Unknown]: US
Is CN=Tom Elrod, OU=Development, O=JBoss Inc, L=Atlanta, ST=GA, C=US correct?
[no]: yes

Enter key password for <remoting>
(RETURN if same as keystore password):

Since did not specify the -keystore filename parameter, created the keystore in $HOME/.keystore (or C:\Documents and Settings\Tom\.keystore).

Export the RSA certificate (without the private key)

C:\tmp\ssl>keytool -export -alias remoting -file remoting.cer
Enter keystore password: opensource
Certificate stored in file <remoting.cer>

Import the RSE certificate into a new truststore file.

C:\tmp\ssl>keytool -import -alias remoting -keystore .truststore -file remoting.cer
Enter keystore password: opensource
Owner: CN=Tom Elrod, OU=Development, O=JBoss Inc, L=Atlanta, ST=GA, C=US
Issuer: CN=Tom Elrod, OU=Development, O=JBoss Inc, L=Atlanta, ST=GA, C=US
Serial number: 426f1ee3
Valid from: Wed Apr 27 01:10:59 EDT 2005 until: Tue Jul 26 01:10:59 EDT 2005
Certificate fingerprints:
MD5: CF:D0:A8:7D:20:49:30:67:44:03:98:5F:8E:01:4A:6A
SHA1: C6:76:3B:6C:79:3B:8D:FD:FB:4F:33:3B:25:C9:01:9D:50:BF:9F:8A
Trust this certificate? [no]: yes
Certificate was added to keystore

Now have two files, .keystore for the server and .truststore for the client.

Common errors when using server socket factory:

javax.net.ssl.SSLException: No available certificate corresponds to the SSL cipher suites
                            which are enabled.

The 'javax.net.ssl.keyStore' system property has not been set and are using the default SSLServerSocketFactory.

java.net.SocketException: Default SSL context init failed: Cannot recover key

The 'javax.net.ssl.keyStorePassword' system property has not been set and are using the default SSLServerSocketFactory.

java.io.IOException: Can not create SSL Server Socket Factory due to the url to the key store
                     not being set.

The default SSLServerSocketFactory is NOT being used (so custom configuration for the server socket factory) and the key store url has not been set.

java.lang.IllegalArgumentException: password can't be null

The default SSLServerSocketFactory is NOT being used (so custom configuration for the server socket factory) and the key store password has not been set.

As with all configuration parameters, there are several avenues for specifying parameter values. See Section General transport configuration for a general discussion of parameter configuration in Remoting. The transport independent key for setting timeouts is "timeout", also available as org.jboss.remoting.ServerInvoker.TIMEOUT. All server invokers also have the getter/setter methods

public int getTimeout();

public void setTimeout(int timeout);

where the values are given in milliseconds. The default timeout value is 60000 for server invokers.

As of version 2.4, all Remoting transports offer a per invocation transport facility, which allows a timeout value to be set for a particular invocation, overriding the client invoker's previously configured timeout value. The per invocation timeout is set by passing the String representation of the timeout value in the invocation's metadata map, using the key "timeout". For example,

HashMap metadata = new HashMap();
metadata.put("timeout", "2000");
client.invoke("testInvocation", metadata);

will allow approximately 2 seconds for this particular invocation, after which the timeout value will be reset to its previously configured value.

Each transport handles per invocation timeouts a little differently. More details are given below.

SERVER_BIND_ADDRESS (actual value is 'jboss.bind.address') - indicates the system property key for bind address that should be used.

BIND_BY_HOST (actual value is 'remoting.bind_by_host') - indicates the system property key for if the local bind address should be by host name (e.g. InetAddress.getLocalHost().getHostName()) or if should be by IP (e.g. InetAddress.getLocalHost().getHostAddress()). The default is 'True', meaning will will use local host name. This configuration only applies when the initial bind address is 0.0.0.0 (or InvokerLocator.ANY).

DATATYPE (actual value is 'datatype') - indicates the marshalling datatype that should be used for a particular invoker. Each invoker has its own default marshaller and unmarshaller based on default datatype. For examle, the socket transport has a default datatype of 'serializable', which is automatically registered with the MarshalFactory and associated by default with org.jboss.remoting.marshal.serializable.SerializableMarshaller and org.jboss.remoting.marshal.serializable.SerializableUnMarshaller. The marshaller and unmarshaller used by an invoker can be overriden by setting the 'datatype' parameter within the LocatorInvoker. For example, could use a locator url of:

socket://myhost:6500/?datatype=test

which would cause the socket invoker to use the marshaller and unmarshaller registered with the MarshalFactory under the datatype 'test'. Of course, this requires that the marshaller and unmarshaller implementations to be used have already been registered with the MarshalFactory (otherwise will get an exception).

SERIALIZATIONTYPE (actual value is 'serializationtype') - indicates the serialization implementation to use. Currently, the only possible values are 'java' and 'jboss'. Java serialization is the default. Setting to 'jboss' will cause JBoss Serialization to be used. In implementation, this equates to the parameter that will be passed to the SerializationStreamFactory.getManagerInstance() method. This configuration can be set as an invoker locator url parameter (e.g. socket://myhost:5400/?serializationtype=jboss) or as an entry to the configuration Map passed when constructing a remoting client or server.

MARSHALLER (actual value is 'marshaller') - used to indicate which marshaller implementation should be used by the invoker. This is an override for whatever the invoker's default implementation is. This can be set as a parameter of the invoker locator url (e.g. socket://myhost:6500/?marshaller=org.jboss.test.remoting.marshall.dynamic.remote.http.TestMarshaller). Using this configuration requires that the value be the fully qualified classname of the marshaller implementation to use (which must be on the classpath, have a void constructor, and implement the org.jboss.remoting.marshal.Marshaller interface).

UNMARSHALLER (actual value is 'unmarshaller') - used to indicate which unmarshaller implementation should be used by the invoker. This is an override for whatever the invoker's default implementation is. This can be set as a parameter of the invoker locator url (e.g. socket://myhost:6500/?unmarshaller=org.jboss.test.remoting.marshall.dynamic.remote.http.TestUnMarshaller). Using this configuration requires that the value be the fully qualified classname of the unmarshaller implementation to use (which must be on the classpath, have a void constructor, and implement the org.jboss.remotng.marshal.UnMarshaller interface).

LOADER_PORT (actual value is 'loaderport') - indicates the port number where the class loader server resides. This can be used when is possible that a client may not have particular classes locally and would want to load them from the server dynamically. This property can be set as a parameter to the invoker locator url. A clasic example of when this might be used would be in conjunction with using custom marshalling. For example, if have configured a server to use custom marshaller and unmarshaller that the client will not have access to, could create a invoker locator such as:

socket://myhost:6500/?datatype=test&loaderport=6501&
        marshaller=org.jboss.test.remoting.marshall.dynamic.remote.http.TestMarshaller&
        unmarshaller=org.jboss.test.remoting.marshall.dynamic.remote.http.TestUnMarshaller

When the client invoker begins to make an invocation, will try to look up marshaller and unmarshaller based on type ('test' in this case) and when can not find a registry entry for it, will try to load the TestMarshaller and TestUnMarshaller from the classpath. When the classes can not be found locally, will make a call to the loader server (on port 6501) to load the classes locally. Once they are retrieved from the server, will be registered locally, so is a one time only event (as next time will be found in the registry).

This can work for loading any remote server classes, but requires the loaderport be included in the invoker locator url.

BYVALUE (actual value is 'byvalue') - indicates if when making local invocations (meaning client and server invoker exists within same jvm), the marshalling will be done by value, instead of the default, by reference. Using this configuration, the marshalling will actually perform a clone of the object instance (see org.jboss.remoting.serialization.SerializationManager.createMarshalledValueForClone()). Value for this property should be of type String and be either 'true' or 'false'. In releases prior to 2.0.0, using this configuration setting would have forced invokers to be remote, which can now be done via FORCE_REMOTE config (see below).

FORCE_REMOTE (actual value is 'force_remote') - indicates if when making local invocations (meaning client and server invoker exists within same jvm), the remote invokers should be used instead of local invoker. Is equivalent to making invocations as though client and server were in different jvms). Value for this property should be of type String and be either 'true' or 'false'.

CLIENT_LEASE (actual value is 'leasing') - indicates if client should try to automatically establish a lease with the server. Is false by default. Value for this property should be of type String and be either 'true' or 'false'.

CLIENT_LEASE_PERIOD (actual value is 'lease_period') - defines what the client lease period should be in the case that server side leasing is turned on. Value for this parameter key should be the number of milliseconds to wait before each client lease renewal and must be greater than zero in order to be recognized. If this property is not set (and CLIENT_LEASE is), will use the lease period as specified by the server.

SUPPRESS_HOST_WARNING (actual value is 'suppressHostWarning') - the boolean valued system property that determines if InvokerLocator should log a warning that the hostname is null. The default value is "false", i.e., the warning is logged by default.

RAW (actual value is 'rawPayload') - key to use for the metadata Map passed when making an invoke() call and wish for the invocation payload to be sent as is and not wrapped within a remoting invocation request object. This should be used when want to make direct calls on systems outside of remoting (e.g. making an http POST request to a web service).

ENABLE_LEASE (actual value is 'enableLease') - key for the configuration map passed to the Client constructor to indicate that client should make initial request to establish lease with server. The value for this should be either a String that java.lang.Boolean can evaluate or a java.lang.Boolean. By default, leasing is turned off, so this property would be used to turn on leasing for the client.

HANDSHAKE_COMPLETED_LISTENER (actual value is 'handshakeCompletedListener') - key for the configuration map passed to the Client constructor providing a ssl javax.net.ssl.HandshakeCompletedListener implementation, which will be called on when ssl handshake completed with server.

USE_ALL_PARAMS (actual value is 'useAllParameters') - used by org.jboss.remoting.ConnectionValidator and org.jboss.remoting.callback.CallbackPoller to determine if configuration parameters should be retrieved from the InvokerLocator or the Client's configuration map.

The following three configuration properties are only useful when using one of the following Client methods:

public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata,
        Object callbackHandlerObject) throws Throwable
public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata,
        Object callbackHandlerObject, boolean serverToClient) throws Throwable

CALLBACK_SERVER_PROTOCOL (actual value is 'callbackServerProtocol') - key for the configuration when adding a callback handler and internal callback server connector is created. The value should be the transport protocol to be used. By default will use the same protocol as being used by this client (e.g. http, socket, rmi, etc.).

CALLBACK_SERVER_HOST (actual value is 'callbackServerHost') - key for the configuration when adding a callback handler and internal callback server connector is created. The value should be the host name to be used. By default will use the result of calling InetAddress.getLocalHost().getHostAddress().

CALLBACK_SERVER_PORT (actual value is 'callbackServerPort') - key for the configuration when adding a callback handler and internal callback server connector is created. The value should be the port to be used. By default will find a random unused port.

Bean properties (meaning have getter/setter):

SessionId - session id used when making invocations on server invokers. There is a default unique id automatically generated for each Client instance, so unless you have a good reason to set this, do not set this.

Subsystem - the subsystem being used when routing invocation requests on the server side. Specifing a subsystem is only needed when server has multiple handlers registered (which will each have their own associated subsystem). Best if specified using Client constructor.

MaxNumberOfThreads - the maximum number of threads to use within client pool for one way invocations on the client side (meaning oneway invocation is handled by thread in this pool and user's call returns immediately) Default value is MAX_NUM_ONEWAY_THREADS (whose value is 10).

OnewayThreadPool - the thread pool being used for making one way invocations on the client side. If one has not been specifically set via configuration or call to set it, will always return instance of org.jboss.util.threadpool.BasicThreadPool.

SocketFactory - instance of javax.net.SocketFactory, which can only be set on the Client before the connect() method has been called. Otherwise, a runtime exception will be thrown.

Marshaller - the marshaller implementation that should be used by the client invoker (transport). This overrides the client's default marshaller (or any set within configuration).

UnMarshaller - the unmarshaller implementation that should be used by the client invoker (transport). This overrides the client's default unmarshaller (or any set within configuration).

CUSTOM_SERVER_SOCKET_FACTORY (actual value is 'customServerSocketFactory') - key for the configuration map passed to a Connector to indicate the server socket factory to be used. This will override the creation of any other socket factory. Value must be an instance of javax.net.ServerSocketFactory.

CUSTOM_SOCKET_FACTORY (actual value is 'customSocketFactory') - key for the configuration map passed to a Client to indicate the socket factory to be used. Value must be instance of javax.net.SocketFactory.

SOCKET_FACTORY_CLASS_NAME (actual value is 'socketFactoryClassName') - key for the configuration map passed to a Client to indicate the classname of the socket factory to be used. Value should be fully qualified classname of class that is an instance of javax.net.SocketFactory and has a void constructor. This property will not be used if CUSTOM_SOCKET_FACTORY is also set.

SOCKET_CREATION_CLIENT_LISTENER (actual value is "socketCreationClientListener") - key for the configuration map passed to a Client or Connector to indicate a socket creation listener for sockets created by a SocketFactory.

SOCKET_CREATION_SERVER_LISTENER (actual value is "socketCreationServerListener") - key for the configuration map passed to a Client or Connector to indicate a socket creation listener for sockets created by a ServerSocket.

CLIENT_ADDRESS (actual value is "clientAddress") - key with which host address of client will be associated in InvocationRequest request payload.

REMOTING_VERSION (actual value is "remotingVersion") - key for configuring Remoting wire version.

SKIP_ACCESS_CONTROL (actual value is "skipAccessControl") - key for telling Remoting to execute security sensitive code outside of java.security.AccessController.doPrivileged() calls..

CONFIG_OVERRIDES_LOCATOR (actual value is "configOverridesLocator") - key for indicating that parameter values found in the configuration map passed to an org.jboss.remoting.Client constructor should take precedence over values found in the InvokerLocator.

USE_CLIENT_CONNECTION_IDENTITY (actual value "useClientConnectionIdentity") - tells Remoting to adhere to the new "connection identity" semantics described in Chapter Network Connection Monitoring.

PASS_CONFIG_MAP_TO_MARSHAL_FACTORY (actual value "passConfigMapToMarshalFactory") - if set to "true", tells clients and servers to take parameters for configuring marshallers and unmarshallers from the configuration map passed to Clients and Connectors in addition to the parameters in the InvokerLocator.

MAX_NUM_ONEWAY_THREADS_KEY (actual value is 'maxNumThreadsOneway') - key for the maximum number of threads to be used in the thread pool for one way invocations (server side). This property is only used when the default oneway thread pool is used.

ONEWAY_THREAD_POOL_CLASS_KEY (actual value is 'onewayThreadPool') - key for setting the setting the oneway thread pool to use. The value used with this key will first be checked to see if is a JMX ObjectName and if so, try to look up associated mbean for the ObjectName given and cast to type org.jboss.util.threadpool.ThreadPoolMBean (via MBeanServerInvocationHandler.newProxyInstance()). If the value is not a JMX ObjectName, will assume is a fully qualified classname and load the coresponding class and create a new instance of it (which will require it to have a void constructor). The newly created instance will then be cast to type of org.jboss.util.threadpool.ThreadPool.

SERVER_BIND_ADDRESS_KEY (actual value is 'serverBindAddress') - key for setting the address the server invoker should bind to. The value can be either host name or IP.

CLIENT_CONNECT_ADDRESS_KEY (actual value is 'clientConnectAddress') - key for setting the address the client invoker should connecto to. This should be used when client will be connecting to server from outside the server's network and the external address is different from that of the internal address the server invoker will bind to (e.g. using NAT to expose different external address). This will mostly be useful when client uses remoting detection to discover remoting servers. The value can be either host name or IP.

SERVER_BIND_PORT_KEY (actual value is 'serverBindPort') - key for setting the port the server invoker should bind to. If the value supplied is less than or equal to zero, the server invoker will randomly choose a free port to use.

CLIENT_CONNECT_PORT_KEY (actual value is 'clientConnectPort') - key for setting the port the client invoker should connect to. This should be used when client will be connecting to server from outside the server's network and the external port is different from that of the internal port the server invoker will bind to (e.g. using NAT to expose different port routing). This will be mostly useful when client uses remoting detection to discover remoting servers.

CLIENT_LEASE_PERIOD (actual value is 'clientLeasePeriod') - key used for setting the amount of time (in milliseconds) that a client should renew its lease. If this value is not set, the default of five seconds (see DEFAULT_CLIENT_LEASE_PERIOD), will be used. This value will also be what is given to the client when it initially queries server for leasing information.

TIMEOUT (actual value is 'timeout') - key for setting the timeout value (in milliseconds) for socket connections.

SERVER_SOCKET_FACTORY (actual value is 'serverSocketFactory') - key for setting the value for the server socket factory to be used by the server invoker. The value can be either a JMX Object name, in which case will lookup the mbean and create a proxy to it with type of org.jboss.remoting.security.ServerSocketFactoryMBean (via MBeanServerInvocationHandler.newProxyInstance()), or, if not a JMX ObjectName, will assume is the fully qualified classname to the implementation to be used and will load the class and create a new instance of it (which requires it to have a void constructor). The instance will then be cast to type javax.net.ServerSocketFactory.

BLOCKING_MODE (actual value is "blockingMode"): if set to ServerInvoker.BLOCKING (actual value "blocking"), org.jboss.remoting.Client.getCallbacks() will do blocking pull callbacks and CallbackPoller will do blocking polled callbacks; if set to ServerInvoker.NONBLOCKING (actual value "nonblocking"), Client.getCallbacks() will do non-blocking pull callbacks and CallbackPoller will do non-blocking polled callbacks.

BLOCKING_TIMEOUT (actual value is "blockingTimeout"): the timeout value used for blocking callback.

REGISTER_CALLBACK_LISTENER (actual value is "registerCallbackListener"): determines if org.jboss.remoting.callback.ServerInvokerCallbackHandlers should register as org.jboss.remoting.ConnectionListeners with leases. The default value is "true".

Bean properties (meaning have getter/setter):

ServerSocketFactory - implementation of javax.net.ServerSocketFactory to be used by the server invoker. This takes precedence over any other configuration for the server socket factory.

Timeout - timeout (in milliseconds) for socket connection. If set after create() method called, this value will override value set by TIMEOUT key.

LeasePeriod - the amount of time (in milliseconds) that a client should renew its lease. If this value is not set, the default of five seconds (see DEFAULT_CLIENT_LEASE_PERIOD), will be used. This value will also be what is given to the client when it initially queries server for leasing information. If set after create() method called, this value will override value set by CLIENT_LEASE_PERIOD key.

MaxNumberOfOnewayThreads - the maximum number of threads to be used in the thread pool for one way invocations (server side). This property is only used when the default oneway thread pool is used. If set after create() method called, this value will override value set by MAX_NUM_ONEWAY_THREADS_KEY key.

OnewayThreadPool - the oneway thread pool to use.

CALLBACK_POLL_PERIOD (actual value is 'callbackPollPeriod') - key for setting the frequency (in milliseconds) in which Client's internal callback poller should poll server for waiting callbacks. The default value is five seconds.

CALLBACK_SCHEDULE_MODE (actual value is "scheduleMode"): may be set to either CallbackPoller.SCHEDULE_FIXED_RATE (actual value "scheduleFixedRate") or CallbackPoller.SCHEDULE_FIXED_DELAY (actual value "scheduleFixedDelay"). In either case, polling will take place at approximately regular intervals, but in the former case the scheduler will attempt to perform each poll CALLBACK_POLL_PERIOD milliseconds after the previous attempt, and in the latter case the scheduler will attempt to schedule polling so that the average interval will be approximately CALLBACK_POLL_PERIOD milliseconds. CallbackPoller.SCHEDULE_FIXED_RATE is the default.

REPORT_STATISTICS (actual value is "reportStatistics"): The presence of this key in metadata, regardless of its value, will cause the CallbackPoller to print statistics that might be useful for configuring the other parameters..

SYNCHRONIZED_SHUTDOWN (actual value is "doSynchronizedShutdown"): if set to "true", CallbackPoller.stop() will wait for Client.getCallbacks() to return, and if set to "false" it will not wait. For blocking polled callbacks, the default value is "false" and for non-blocking polled callbacks, the default value is "true".

MAX_ERROR_COUNT (actual value is "maxErrorCount"): determines the maximum number of errors that may be experienced during polling before CallbackPoller will shut itself down. The default value is "5".

CallbackPoller configuration is only necessary when using one of the following Client methods:

public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata,
        Object callbackHandlerObject) throws Throwable
public void addListener(
        InvokerCallbackHandler callbackhandler, Map metadata,
        Object callbackHandlerObject, boolean serverToClient) throws Throwable

The keys should be among the entries in the metadata Map passed. This will also only apply when the underlying transport is uni-directional (e.g. socket, http, rmi). Bi-directional transports will not need to poll.

FILE_PATH_KEY (actual value is 'StoreFilePath') - key for setting the directory in which to write the callback objects. The default value is the property value of 'jboss.server.data.dir' and if this is not set, then will be 'data'. Will then append 'remoting' and the callback client's session id. An example would be 'data\remoting\5c4o05l-9jijyx-e5b6xyph-1-e5b6xyph-2'.

FILE_SUFFIX_KEY (actual value is 'StoreFileSuffix') - key for setting the file suffix to use for the callback objects written to disk. The default value is 'ser'.

CALLBACK_ERRORS_ALLOWED (actual value is 'callbackErrorsAllowed') - key for setting the number of callback exceptions that will be allowed when calling on org.jboss.remoting.callback.InvokerCallbackHandler.handleCallback(Callback callback) before cleaning up the callback listener. This only applies to push callback. The default if this property is not set is five.

CALLBACK_STORE_KEY (actual value is 'callbackStore') - key for specifing the callback store to be used. The value can be either a JMX ObjectName or a fully qualified class name; either way, must implement org.jboss.remoting.SerializableStore. If using class name, the callback store implementation must have a void constructor. The default is to use the org.jboss.remoting.callback.NullCallbackStore.

CALLBACK_ERROR_HANDLER_KEY (actual value is 'callbackErrorHandler') - key for specifing the callback exception handler to be used. The value can be either a JMX ObjectName or a fully qualified class name, either way, must implement org.jboss.remoting.callback.CallbackErrorHandler. If using class name, the callback exception handler implementation must have a void constructor. The default is to use org.jboss.remoting.callback.DefaultCallbackErrorHandler.

CALLBACK_MEM_CEILING (actual value is 'callbackMemCeiling') - key for specifying the percentage of free memory available before callbacks will be persisted. If the memory heap allocated has reached its maximum value and the percent of free memory available is less than the callbackMemCeiling, this will trigger persisting of the callback message. The default value is 20.

CALLBACK_TIMEOUT (actual value is 'callbackTimeout') - key for specifying the timeout to be used for doing push callbacks. In the absence of ServerInvokerCallbackHandler.CALLBACK_TIMEOUT, the timeout value configured for the Connector will be used.

Bean properties (meaning have getter/setter):

SubContextName - sub context name under which detection messages will be bound and looked up.

PRESERVE_LINES (actual value is "preserveLines"): the key used to turn on or off HTTPUnMarshaller's behavior of stripping CR/LF characters.

IS_CALLBACK_SERVER (actual value is "isCallbackServer"): when a bisocket server invoker receives this parameter with a value of true, it avoids the creation of a ServerSocket. Therefore, IS_CALLBACK_SERVER should be used on the client side for the creation of a callback server. The default value is false.

PING_FREQUENCY (actual value is "pingFrequency"): The server side uses this value to determine the interval, in milliseconds, between pings that it will send on the control connection. The client side uses this value to calculate the window in which it must receive pings on the control connection. In particular, the window is ping frequency * ping window factor. See also the definition of PING_WINDOW_FACTOR. The default value is 5000.

PING_WINDOW_FACTOR (actual value is "pingWindowFactor"): The client side uses this value to calculate the window in which it must receive pings on the control connection. In particular, the window is ping frequency * ping window factor. See also the definition of PING_FREQUENCY. The default value is 2.

MAX_RETRIES (actual value is "maxRetries"): This parameter is relevant only on the client side, where the BisocketClientInvoker uses it to govern the number of attempts it should make to get the address and port of the secondary ServerSocket, and the BisocketServerInvoker uses it to govern the number of attempts it should make to create both ordinary and control sockets. The default value is 10.

SECONDARY_BIND_PORT (actual value is "secondaryBindPort"): The server side uses this parameter to determine the bind port for the secondary ServerSocket.

SECONDARY_BIND_PORTS (actual value is "secondaryBindPorts"): The server side uses this parameter to determine the bind ports for the secondary ServerSockets in a multihome server.

SECONDARY_CONNECT_PORT (actual value is "secondaryConnectPort"): The server side uses this parameter to determine the connect port used by the client side to connect to the secondary ServerSocket.

SECONDARY_CONNECT_PORTS (actual value is "secondaryConnectPorts"): The server side uses this parameter to determine the connect ports used by the client side to connect to the secondary ServerSockets in a multihome server.

SECONDARY_MAX_THREADS (actual value is "secondaryMaxThreads"): Determines the maximum number of sockets accepted by the secondary ServerSocket that can be processed simultaneously. Introduced in release 2.5.4.SP2. Default value is 50.

SECONDARY_TIMEOUT (actual value is "secondaryTimeout"): Determines the timeout used when reading initial data from a socket accepted by the secondary ServerSocket. Introduced in release 2.5.4.SP2. Default value is 60000 ms.

"executor": a comma separated list of attributes associated with this key will be used to configure an org.apache.catalina.core.StandardThreadExecutor, which will then be injected into the underlying Coyote Connector. See http://tomcat.apache.org/tomcat-6.0-doc/config/executor.html. for the available configurable attributes.

DISCONNECT_AFTER_USE (actual value is "disconnectAfterUse") - key indicating if the java.net.HttpURLConnection should be disconnected after the invocation. The default value is "false".

IGNORE_ERROR_RESPONSE_MESSAGE (actual value is "ignoreErrorResponseMessage") - key indicating if org.jboss.remoting.transport.http.HTTPClientInvoker should try to get a response message and response code in the event of an exception. The default value is "false".

NUMBER_OF_CALL_ATTEMPTS (actual value is "numberOfCallAttempts"): This parameter is relevant only on the client side, where it determines the maximum number of attempts that will be made to complete an invocation. The default value is 1.

UNMARSHAL_NULL_STREAM (actual value is "unmarshalNullStream") - key indicating if org.jboss.remoting.transport.http.HTTPClientInvoker should make the call to UnMarshaller.read() when the InputStream is null. The default value is "true".

The following are keys to use to get corresponding values from the Map returned from call to org.jboss.remoting.InvocationRequest.getRequestPayload() within a org.jboss.remoting.ServerInvocationHandler implementation. For example:

public Object invoke(InvocationRequest invocation) throws Throwable
{
   Map headers = invocation.getRequestPayload();
   ...

where variable 'headers' will contain entries for the following keys.

METHODTYPE (actual value is 'MethodType') - key for getting the method type used by client in http request. This will be populated within the Map returned from call to org.jboss.remoting.InvocationRequest.getRequestPayload() within a org.jboss.remoting.ServerInvocationHandler implementation. For example:

public Object invoke(InvocationRequest invocation) throws Throwable
{
   Map headers = invocation.getRequestPayload();
   String methodType = (String) headers.get(HTTPMetadataConstants.METHODTYPE);
   if(methodType != null)
   {
      if(methodType.equals("GET"))
      ...

PATH (actual value is 'Path') - key for getting the path from the url request from the calling client. This will be populated within the Map returned from call to org.jboss.remoting.InvocationRequest.getRequestPayload() within a org.jboss.remoting.ServerInvocationHandler implementation. For example:

public Object invoke(InvocationRequest invocation) throws Throwable
{
   Map headers = invocation.getRequestPayload();
   String path = (String) headers.get(HTTPMetadataConstants.PATH);
   ...

HTTPVERSION (actual value is 'HttpVersion') - key for getting the HTTP version from the calling client request (e.g. HTTP/1.1).

RESPONSE_CODE (actual value is 'ResponseCode') - key for getting and setting the HTTP response code. Will be used as key to get the response code from metadata Map passed to the Client's invoke() method after the invocation has been made. For example:

Map metadata = new HashMap();
Object response = remotingClient.invoke(myPayloadObject, metadata);
Integer responseCode = (Integer) metadata.get(HTTPMetadataConstants.RESPONSE_CODE);

Will be used as key to put the response code in the return payload map from invocation handler. For example:

public Object invoke(InvocationRequest invocation) throws Throwable
{
   Map responseHeaders = invocation.getReturnPayload();
   responseHeaders.put(HTTPMetadataConstants.RESPONSE_CODE, new Integer(202)); 

RESPONSE_CODE_MESSAGE (actual value is 'ResponseCodeMessage') - key for getting and setting the HTTP response code message. Will be used as the key to get the response code message from metadata Map passed to the Client's invoke() method after the invocation has been made. For example:

Map metadata = new HashMap();
Object response = remotingClient.invoke(myPayloadObject, metadata);
String responseCodeMessage = (String) metadata.get(HTTPMetadataConstants.RESPONSE_CODE_MESSAGE);

Will be used as key to put the response code message in the return payload map from invocation handler. For example:

public Object invoke(InvocationRequest invocation) throws Throwable
{
   Map responseHeaders = invocation.getReturnPayload();
   responseHeaders.put(
           HTTPMetadataConstants.RESPONSE_CODE_MESSAGE,
           "Custom response code and message from remoting server");

RESPONSE_HEADERS (actual value is 'ResponseHeaders') - key for returning the value of java.net.URLConnection.getHeaderFields(). In other words, a map containing all of the response headers is stored in the metadata map. For example,

Object payload = ... ;
HashMap metadata = new HashMap();
client.invoke(payload, metadata);
Map responseHeaders = (Map) metadata.get(HTTPMetadataConstants.RESPONSE_HEADERS);

NO_THROW_ON_ERROR (actual value is 'NoThrowOnError') - key indicating if http client invoker (for transports http, https, servlet, and sslservlet) should throw an exception if the server response code is equal to or greater than 400. Unless set to true, the client invoker will by default throw either the exception that originated on the server (if using remoting server) or throw a org.jboss.remoting.transport.http.WebServerError, whose message will be the error html returned from the web server.

DONT_RETURN_EXCEPTION (actual value is 'dont-return-exception') - key indicating if org.jboss.remoting.transport.servlet.ServletServerInvoker should revert to the orginal error handling behavior of returning an error message.

USE_REMOTING_CONTENT_TYPE (actual value is 'useRemotingContentType') - key indicating if org.jboss.remoting.marshal.http.HTTPUnMarshaller should determine that it is reading a String by using the "content-type" return header (if set to "false") or the "remotingContentType" header if set to "true". The default value is "false", to avoid introducing any inconsistent behavior between versions, but, if the org.jboss.remoting.ServerInvocationHandler sets the content-type return header, then this parameter should be set to "true".

For every http client request made from remoting client, a remoting version and remoting specific user agent will be set as a request property. The request property key for the remoting version will be 'JBoss-Remoting-Version' and the value will be set based on return from call to Version.getDefaultVersion(). The 'User-Agent' request property value will be set to the evaluation of '"JBossRemoting - " + Version.VERSION'.

IGNORE_HTTPS_HOST (actual value is 'org.jboss.security.ignoreHttpsHost') - key indicating if the http client invoker (for transports https and sslservlet) should ignore host name verification (meaning will not check for URL's hostname and server's identification hostname mismatch during handshaking). By default, if this not set to true, standard hostname verification will be performed.

HOSTNAME_VERIFIER (actual value is 'hostnameVerifier') - key indicating the hostname verifier that should be used by the http client invoker. The value should be the fully qualified classname of class that implements javax.net.ssl.HostnameVerifier and has a void constructor.

USE_DEFAULT_SSL_SOCKET_FACTORY (actual value is 'useDefaultSslSocketFactory') - if set to true, then HTTPSClientInvoker.createSocketFactory() will call HttpsURLConnection.getDefaultSSLSocketFactory() instead of trying to build a SocketFactory.

REGISTRY_PORT_KEY (actual value is 'registryPort') - the port on which to create the RMI registry. The default is 3455. This also needs to have the isParam attribute set to true.

RMI_ONEWAY_MARSHALLING (actual value is 'rmiOnewayMarshalling') - if set to "true" will cause the RMI transport to use the original client to server marshalling behavior.

UNWRAP_SINGLETON_ARRAYS (actual value is 'unwrapSingletonArrays') - If the map returned by javax.servlet.http.HttpServletRequest.getParameterMap() maps a String key to an array of length one, the value in the array will be extracted and associated with the key.

TCP_NODELAY_FLAG (actual value is 'enableTcpNoDelay') - can be either true or false and will indicate if client socket should have TCP_NODELAY turned on or off. TCP_NODELAY is for a specific purpose; to disable the Nagle buffering algorithm. It should only be set for applications that send frequent small bursts of information without getting an immediate response; where timely delivery of data is required (the canonical example is mouse movements). The default is false.

MAX_POOL_SIZE_FLAG (actual value is 'clientMaxPoolSize') - the client side maximum number of threads. The default is 50.

CLIENT_SOCKET_CLASS_FLAG (actual value is 'clientSocketClass') - specifies the fully qualified class name for the custom SocketWrapper implementation to use on the client. Note, will need to make sure this is marked as a client parameter (using the 'isParam' attribute). Making this change will not affect the marshaller/unmarshaller that is used, which may also be a requirement.

USE_ONEWAY_CONNECTION_TIMEOUT (actual value "useOnewayConnectionTimeout") - indicates if, during a client side oneway invocation, MicroSocketClientInvoker should wait for a version byte from the server, which prevents the anomalous behavior described in JBREM-706 "In socket transport, prevent client side oneway invocations from artificially reducing concurrency". The default value is "true".

EVICTABILITY_TIMEOUT (actual value "evictabilityTimeout") - indicates the number of milliseconds during which a server thread waiting for the next invocation will not be preemptible.

CONTINUE_AFTER_TIMEOUT (actual value "continueAfterTimeout") - indicates what a server thread should do after experiencing a java.net.SocketTimeoutException. If set to "true", or if JBossSerialization is being used, the server thread will continue to wait for an invocation; otherwise, it will return itself to the thread pool.

CHECK_CONNECTION_KEY (actual value is 'socket.check_connection') - key for indicating if socket invoker should continue to keep socket connection between client and server open after invocations by sending a ping on the connection before being re-used. The default for this is false.

SERVER_SOCKET_CLASS_FLAG (actual value is 'serverSocketClass') - specifies the fully qualified class name for the custom SocketWrapper implementation to use on the server.

Bean properties (meaning have getter/setter):

acceptThreadPriorityIncrement - can be used to increment the priority of the accept thread, which manages the ServerSocket. The value is added to java.lang.Thread.NORM_PRIORITY, and the resulting value must be no more than java.lang.Thread.MAX_PRIORITY. This parameter might be useful on a heavily loaded machine if the accept thread is getting starved.

ImmediateShutdown - a flag for indicating that SocketServerInvoker should shut down all of its ServerThreads immediately instead of waiting for any current invocations to finish.

WRITE_TIMEOUT (actual value is 'writeTimeout') - key for configuring the "write timeout" facility. If set to a value greater than 0, then a write operation that does not complete within the configured number of milliseconds will be terminated and the socket will be closed. The default value is -1.