org.infinispan.statetransfer

Class StateRequestCommand

java.lang.Object

org.infinispan.commands.remote.BaseRpcCommand

org.infinispan.statetransfer.StateRequestCommand

All Implemented Interfaces:

CacheRpcCommand, ReplicableCommand

public class StateRequestCommand
extends BaseRpcCommand

This command is used by a StateConsumer to request transactions and cache entries from a StateProvider.

Since:

5.2

Author:

anistor@redhat.com

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	StateRequestCommand.Type

Field Summary

Fields

Modifier and Type	Field and Description
static byte	COMMAND_ID

Fields inherited from class org.infinispan.commands.remote.BaseRpcCommand

cacheName

Constructor Summary

Constructors

Constructor and Description
StateRequestCommand(String cacheName)
StateRequestCommand(String cacheName, StateRequestCommand.Type type, Address origin, int topologyId, Set<Integer> segments)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	canBlock() If true, the command is processed asynchronously in a thread provided by an Infinispan thread pool.
byte	getCommandId() Used by marshallers to convert this command into an id for streaming.
Object[]	getParameters() Used by marshallers to stream this command across a network
Set<Integer>	getSegments()
int	getTopologyId()
StateRequestCommand.Type	getType()
void	init(StateProvider stateProvider)
boolean	isReturnValueExpected() If true, a return value will be provided when performed remotely.
Object	perform(InvocationContext ctx) Performs the primary function of the command.
void	setParameters(int commandId, Object[] parameters) Used by the CommandsFactory to create a command from raw data read off a stream.
String	toString()

Methods inherited from class org.infinispan.commands.remote.BaseRpcCommand

getCacheName, getOrigin, setOrigin

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

COMMAND_ID

public static final byte COMMAND_ID

See Also:

Constant Field Values

Constructor Detail

StateRequestCommand

public StateRequestCommand(String cacheName)

StateRequestCommand

public StateRequestCommand(String cacheName,
                   StateRequestCommand.Type type,
                   Address origin,
                   int topologyId,
                   Set<Integer> segments)

Method Detail

init

public void init(StateProvider stateProvider)

perform

public Object perform(InvocationContext ctx)
               throws Throwable

Description copied from interface: ReplicableCommand

Performs the primary function of the command. Please see specific implementation classes for details on what is performed as well as return types. Important: this method will be invoked at the end of interceptors chain. It should never be called directly from a custom interceptor.

Parameters:

ctx - invocation context

Returns:

arbitrary return value generated by performing this command

Throws:

Throwable - in the event of problems.

isReturnValueExpected

public boolean isReturnValueExpected()

Description copied from interface: ReplicableCommand

If true, a return value will be provided when performed remotely. Otherwise, a remote ResponseGenerator may choose to simply return null to save on marshalling costs.

Returns:

true or false

canBlock

public boolean canBlock()

Description copied from interface: ReplicableCommand

If true, the command is processed asynchronously in a thread provided by an Infinispan thread pool. Otherwise, the command is processed directly in the JGroups thread.

This feature allows to avoid keep a JGroups thread busy that can originate discard of messages and retransmissions. So, the commands that can block (waiting for some state, acquiring locks, etc.) should return true.

Specified by:

canBlock in interface ReplicableCommand

Overrides:

canBlock in class BaseRpcCommand

Returns:

true if the command can block/wait, false otherwise

getType

public StateRequestCommand.Type getType()

getTopologyId

public int getTopologyId()

getSegments

public Set<Integer> getSegments()

getCommandId

public byte getCommandId()

Description copied from interface: ReplicableCommand

Used by marshallers to convert this command into an id for streaming.

Returns:

the method id of this command. This is compatible with pre-2.2.0 MethodCall ids.

getParameters

public Object[] getParameters()

Description copied from interface: ReplicableCommand

Used by marshallers to stream this command across a network

Returns:

an object array of arguments, compatible with pre-2.2.0 MethodCall args.

setParameters

public void setParameters(int commandId,
                 Object[] parameters)

Description copied from interface: ReplicableCommand

Used by the CommandsFactory to create a command from raw data read off a stream.

Parameters:

commandId - command id to set. This is usually unused but *could* be used in the event of a command having multiple IDs, such as PutKeyValueCommand.

parameters - object array of args

toString

public String toString()

Overrides:

toString in class BaseRpcCommand