org.infinispan.statetransfer

Class StateRequestCommand

java.lang.Object

org.infinispan.commands.remote.BaseRpcCommand

org.infinispan.statetransfer.StateRequestCommand

All Implemented Interfaces:

CacheRpcCommand, ReplicableCommand, TopologyAffectedCommand

public class StateRequestCommand
extends BaseRpcCommand
implements TopologyAffectedCommand

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

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.
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	readFrom(ObjectInput input) Reads this instance from the stream written by ReplicableCommand.writeTo(ObjectOutput).
void	setTopologyId(int topologyId)
String	toString()
void	writeTo(ObjectOutput output) Writes this instance to the ObjectOutput.

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

Methods inherited from interface org.infinispan.commands.ReplicableCommand

getParameters, setParameters

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.

Specified by:

perform in interface ReplicableCommand

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.

Specified by:

isReturnValueExpected in interface ReplicableCommand

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()

Specified by:

getTopologyId in interface TopologyAffectedCommand

setTopologyId

public void setTopologyId(int topologyId)

Specified by:

setTopologyId in interface TopologyAffectedCommand

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.

Specified by:

getCommandId in interface ReplicableCommand

Returns:

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

writeTo

public void writeTo(ObjectOutput output)
             throws IOException

Description copied from interface: ReplicableCommand

Writes this instance to the ObjectOutput.

Specified by:

writeTo in interface ReplicableCommand

Parameters:

output - the stream.

Throws:

IOException - if an error occurred during the I/O.

readFrom

public void readFrom(ObjectInput input)
              throws IOException,
                     ClassNotFoundException

Description copied from interface: ReplicableCommand

Reads this instance from the stream written by ReplicableCommand.writeTo(ObjectOutput).

Specified by:

readFrom in interface ReplicableCommand

Parameters:

input - the stream to read.

Throws:

IOException - if an error occurred during the I/O.

ClassNotFoundException - if it tries to load an undefined class.

toString

public String toString()

Overrides:

toString in class BaseRpcCommand