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현재 Web Beans RI는 JBoss AS 5에서만 실행됩니다; RI를 기타 다른 EE 환경 (예를 들어 Glassfish와 같은 다른 애플리케이션 서버)으로 통합, 또는 servlet 컨테이너로 통합 (예: Tomcat), 또는 내장된 EJB3.1 구현과 통합하는 것은 쉽습니다. Appendix에서 필요한 절차에 대해 간략하게 살펴보겠습니다.
SE 환경에서 Web Beans를 실행할 수 있어야 하지만, 자체적 컨텍스트 및 수명 주기 추가와 같은 더 많은 작업을 해야 합니다. 현재 Web Beans RI는 수명 확장 지점을 나타내지 않고 있으므로, Web Beans RI 클래스에 대해 직접 코드화해야 합니다.
Web Beans SPI는 webbeans-ri-spi 모듈에 위치하고 있으며 webbeans-ri-spi.jar로 패키징되어 있습니다. 일부 SPI는 옵션 사항이며, 기본값 동작을 덮어쓰기해야할 경우, 다른 사항이 필요합니다.
SPI에 있는 모든 인터페이스는 데코레이터 패턴을 지원하고 Forwarding 클래스를 제공합니다.
public interface WebBeanDiscovery {
/**
* Gets list of all classes in classpath archives with web-beans.xml files
*
* @return An iterable over the classes
*/
public Iterable<Class<?>
> discoverWebBeanClasses();
/**
* Gets a list of all web-beans.xml files in the app classpath
*
* @return An iterable over the web-beans.xml files
*/
public Iterable<URL
> discoverWebBeansXml();
}
Web Bean 클래스 및 web-bean.xml 파일 검색은 쉽게 알 수 있습니다 (알고리즘은 JSR-299 사양 11.1장에 설명되어 있으므로 여기서 다시 설명하지 않습니다).
Web Beans RI는 컨테이너로 EJB3 bean 검색을 위임하므로 EJB3 어노테이션을 검색하거나 ejb-jar.xml을 파싱할 필요가 없습니다. 애플리케이션에 있는 각각의 EJB의 경우 EJBDescriptor를 검색해야 합니다:
public interface EjbDiscovery
{
public static final String PROPERTY_NAME = EjbDiscovery.class.getName();
/**
* Gets a descriptor for each EJB in the application
*
* @return The bean class to descriptor map
*/
public Iterable<EjbDescriptor<?>
> discoverEjbs();
}
public interface EjbDescriptor<T
> {
/**
* Gets the EJB type
*
* @return The EJB Bean class
*/
public Class<T
> getType();
/**
* Gets the local business interfaces of the EJB
*
* @return An iterator over the local business interfaces
*/
public Iterable<BusinessInterfaceDescriptor<?>
> getLocalBusinessInterfaces();
/**
* Gets the remote business interfaces of the EJB
*
* @return An iterator over the remote business interfaces
*/
public Iterable<BusinessInterfaceDescriptor<?>
> getRemoteBusinessInterfaces();
/**
* Get the remove methods of the EJB
*
* @return An iterator over the remove methods
*/
public Iterable<Method
> getRemoveMethods();
/**
* Indicates if the bean is stateless
*
* @return True if stateless, false otherwise
*/
public boolean isStateless();
/**
* Indicates if the bean is a EJB 3.1 Singleton
*
* @return True if the bean is a singleton, false otherwise
*/
public boolean isSingleton();
/**
* Indicates if the EJB is stateful
*
* @return True if the bean is stateful, false otherwise
*/
public boolean isStateful();
/**
* Indicates if the EJB is and MDB
*
* @return True if the bean is an MDB, false otherwise
*/
public boolean isMessageDriven();
/**
* Gets the EJB name
*
* @return The name
*/
public String getEjbName();
}
EjbDescriptor는 쉽게 알 수 있어야 하며 EJB 사양에 정의되어 있음으로 관련된 메타데이터를 반환해야 합니다. 이러한 두 가지 인터페이스에 더하여, 로컬 비지니스 인터페이스를 나타내는 BusinessInterfaceDescriptor가 있습니다. (EJB 인스턴스를 검색하는데 사용되는 인터페이스 클래스 및 jndi 이름을 캡슐화)
The resolution of @EJB, @PersistenceContext and @Resource is delegated to the container. You must provide an implementation of org.jboss.webbeans.ejb.spi.EjbResolver which provides these operations. Web Beans passes in the javax.inject.manager.InjectionPoint the resolution is for, as well as the NamingContext in use for each resolution request.
The Web Beans RI must delegate JTA activities to the container. The SPI provides a couple hooks to easily achieve this with the TransactionServices interface.
public interface TransactionServices
{
/**
* Possible status conditions for a transaction. This can be used by SPI
* providers to keep track for which status an observer is used.
*/
public static enum Status
{
ALL, SUCCESS, FAILURE
}
/**
* Registers a synchronization object with the currently executing
* transaction.
*
* @see javax.transaction.Synchronization
* @param synchronizedObserver
*/
public void registerSynchronization(Synchronization synchronizedObserver);
/**
* Queries the status of the current execution to see if a transaction is
* currently active.
*
* @return true if a transaction is active
*/
public boolean isTransactionActive();
}
The enumeration Status is a convenience for implementors to be able to keep track of whether a synchronization is supposed to notify an observer only when the transaction is successful, or after a failure, or regardless of the status of the transaction.
Any javax.transaction.Synchronization implementation may be passed to the registerSynchronization() method and the SPI implementation should immediately register the synchronization with the JTA transaction manager used for the EJBs.
To make it easier to determine whether or not a transaction is currently active for the requesting thread, the isTransactionActive() method can be used. The SPI implementation should query the same JTA transaction manager used for the EJBs.
Web Beans expects the Application Server or other container to provide the storage for each application's context. The org.jboss.webbeans.context.api.BeanStore should be implemented to provide an application scoped storage. You may find org.jboss.webbeans.context.api.helpers.ConcurrentHashMapBeanStore useful.
The org.jboss.webbeans.bootstrap.api.Bootstrap interface defines the bootstrap for Web Beans. To boot Web Beans, you must obtain an instance of org.jboss.webbeans.bootstrap.WebBeansBootstrap (which implements Boostrap), tell it about the SPIs in use, and then request the container start.
The bootstrap is split into phases, bootstrap initialization and bootstrap. Initialization will create a manager, and add the standard (specification defined) contexts. Bootstrap will discover EJBs, classes and XML; add beans defined using annotations; add beans defined using XML; and validate all beans.
To initialize the bootstrap you call Bootstrap.initialize(). Before calling initialize() you must have called Bootstrap.setEjbResolver(). If you are not using the built in DefaultNamingContext or the built in DefaultResourceLoader you must set these before calling initialize().
Having called initialize(), the Manager can be obtained by calling Bootstrap.getManager().
To boot the container you call Bootstrap.boot(). Before calling boot() you must have called Bootstrap.setWebBeanDiscovery(), Bootstrap.setEjbDiscovery() and Bootstrap.setApplicationContext().
To shutdown the container you call Bootstrap.shutdown(). This allows the container to perform any cleanup operations needed.
The Web Beans RI implements JNDI binding and lookup according to standards, however you may want to alter the binding and lookup (for example in an environment where JNDI isn't available). To do this, implement org.jboss.webbeans.resources.spi.NamingContext:
public interface NamingContext extends Serializable {
/**
* Typed JNDI lookup
*
* @param <T
> The type
* @param name The JNDI name
* @param expectedType The expected type
* @return The object
*/
public <T
> T lookup(String name, Class<? extends T
> expectedType);
/**
* Binds an item to JNDI
*
* @param name The key to bind under
* @param value The item to bind
*/
public void bind(String name, Object value);
}
Web Beans RI는 여러번 classpath에서 클래스 및 리소스를 불러와야 합니다. 기본값으로 RI를 불러오기 위해 사용되었던 동일한 classloader에서 로딩되지만, 일부 환경에서는 작동하지 않을 수 도 있습니다. 이러한 경우, org.jboss.webbeans.spi.ResourceLoader를 구현할 수 있습니다:
public interface ResourceLoader {
/**
* Creates a class from a given FQCN
*
* @param name The name of the clsas
* @return The class
*/
public Class<?> classForName(String name);
/**
* Gets a resource as a URL by name
*
* @param name The name of the resource
* @return An URL to the resource
*/
public URL getResource(String name);
/**
* Gets resources as URLs by name
*
* @param name The name of the resource
* @return An iterable reference to the URLS
*/
public Iterable<URL
> getResources(String name);
}
Java EE / Servlet does not provide any hooks which can be used to provide injection into Servlets, so Web Beans provides an API to allow the container to request JSR-299 injection for a Servlet.
To be compliant with JSR-299, the container should request servlet injection for each newly instantiated servlet after the constructor returns and before the servlet is placed into service.
To perform injection on a servlet call WebBeansManager.injectServlet(). The manager can be obtained from Bootstrap.getManager().
API의 외부 구현에서의 올바른 기능을 실행하게 하기 위해 Web Beans RI이 컨테이너에 위치하게 해야 할 여러 요구 사항이 있습니다
Web Beans RI를 다수의 애플리케이션의 운용을 지원하는 환경으로 통합할 경우, 각각의 Web Beans 애플리케이션에 대한 클래스로더 분리를 자동으로 또는 사용자 설정을 통해 반드시 활성화해야 합니다.
Web Beans를 Servlet 환경으로 통합할 경우, Servlet을 사용하는 각각의 Web Beans 애플리케이션에 대해 자동으로 또는 사용자 설정을 통해 org.jboss.webbeans.servlet.WebBeansListener를 Servlet 청취자로 등록해야 합니다.
If you are integrating the Web Beans into a JSF environment you must register org.jboss.webbeans.servlet.ConversationPropagationFilter as a Servlet listener, either automatically, or through user configuration, for each Web Beans application which uses JSF. This filter can be registered for all Servlet deployment safely.
Web Beans를 EJB 환경으로 통합하고자 할 경우 엔터프라이즈 beans를 사용하는 각각의 Web Beans 애플리케이션 용으로 모든 EJB 애플리케이션에 대해 EJB 인터셉터로서 org.jboss.webbeans.ejb.SessionBeanInterceptor를 자동으로 또는 사용자 설정을 통해 등록해야 합니다.
You must register the SessionBeanInterceptor as the inner most interceptor in the stack for all EJBs.
webbeans-ri.jar Web Beans를 애플리케이션 운용을 지원하는 환경으로 통합하고자 할 경우, webbeans-ri.jar를 애플리케이션 분리 classloader로 삽입해야 합니다. 이는 공유 classloader에서 불러올 수 없습니다.