mChaRM.multichannel
Class receiverStub

java.lang.Object
  |
  +--uka.karmi.rmi.server.RemoteObject
        |
        +--uka.karmi.rmi.server.UnicastRemoteObject
              |
              +--mChaRM.multichannel.stub
                    |
                    +--mChaRM.multichannel.receiverStub

All Implemented Interfaces:

java.lang.Cloneable, receiverStubInterface, uka.karmi.rmi.Remote, stubInterface

Direct Known Subclasses:

RMPReceiverStub, verboseReceiverStub

public class receiverStub

extends stub

implements receiverStubInterface

Instances of this class are used as stubs of the multi-channel on the receiver site. Each receiver connected to a multi-channel will be extended by a stub of such a multi-channel.
This class defines the meta-computations that have to be performed on the receiver side. Each new meta-behavior to be performed on the receiver side can be defined extending this class and overrinding the method receiverSideMetaBehavior.

Since:

Version 1.0

Version:

1.2

Author:

Walter Cazzola (cazzola@disi.unige.it)

Fields inherited from class uka.karmi.rmi.server.RemoteObject

serverRef

Constructor Summary

receiverStub(java.lang.Object myReferent, java.lang.String myKind, java.lang.String myReferentName)
receiverStub constructor.

Method Summary

void	afterReceiverSideMetaBehavior(mChaRMMethodCall msg) it is called after the true invocation and performs meta-computation on the return value in the target locus.
void	beforeReceiverSideMetaBehavior(mChaRMMethodCall msg) it is called before the true invocation and performs meta-computation on the message in the target locus.
java.lang.Object	invoke(mChaRMMethodCall msg) it performs the meta-computation on the receiver side -- calling the method receiverSideMetaBehavior --, then really invoke the method reified by the meta-computationi -- invoking the tInvoke method.
protected java.lang.Object	tInvoke(mChaRMMethodCall msg) it invokes a method with the actual arguments on the receiver side.

Methods inherited from class mChaRM.multichannel.stub

referent, retrieveField, setReferent, setWhoIsMyCore, WhoIsMyCore

Methods inherited from class uka.karmi.rmi.server.UnicastRemoteObject

buildStub, clone, exportObject, exportObject, unexportObject

Methods inherited from class uka.karmi.rmi.server.RemoteObject

equals, hashCode, toString, toStub

Methods inherited from class java.lang.Object

, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface mChaRM.multichannel.stubInterface

retrieveField

Constructor Detail

receiverStub

public receiverStub(java.lang.Object myReferent,
                    java.lang.String myKind,
                    java.lang.String myReferentName)
             throws uka.karmi.rmi.RemoteException,
                    ReceiverStubCannotBeRegisteredAsAServerException,
                    CoreNotFoundException

receiverStub constructor. it initialize the stub, registers it as a remote server, and connect it to the core of the multi-channel.

Parameters:

myReferent - a representant of the stub referent.

myKind - the multi-channel's name.

myReferentName - the referent's name.

Throws:

ReceiverStubCannotBeRegisteredAsAServerException - thrown when the stub cannot be registered as a server.

CoreNotFoundException - thrown when the core of the multi-channel, which the stub is part of, doesn't exist or isn't correctly registered as a server.

Method Detail

invoke

public final java.lang.Object invoke(mChaRMMethodCall msg)
                              throws MethodDoesNotExistException

it performs the meta-computation on the receiver side -- calling the method receiverSideMetaBehavior --, then really invoke the method reified by the meta-computationi -- invoking the tInvoke method. It is called by the coreMetaBehavior method of the multi-channel core. It cannot be overrode.
Note that as side-effect the receiverSideMetaBehavior method can change the value of the arguments used by tInvoke.

Specified by:

invoke in interface receiverStubInterface

Parameters:

msg - the hijacked method call.

Returns:

the result of the method invocation

Throws:

MethodDoesNotExistException - thrown when the method reified doesn't exist in the referent class.

tInvoke

protected final java.lang.Object tInvoke(mChaRMMethodCall msg)
                                  throws MethodDoesNotExistException

it invokes a method with the actual arguments on the receiver side. it uses the reflection mechanism offered by the Java API Core Reflection. It is able to handle overloaded method. It cannot neither be overrode nor directly invoked by user.

Parameters:

msg - the hijacked method call.

Returns:

the result of the method invocation.

Throws:

MethodDoesNotExistException - thrown when the method reified doesn't exist in the referent class.

beforeReceiverSideMetaBehavior

public void beforeReceiverSideMetaBehavior(mChaRMMethodCall msg)

it is called before the true invocation and performs meta-computation on the message in the target locus. as default nothing it is done, it is possible to define new behavior defing a new subclass overriding this method.

Parameters:

msg - the hijacked method call.

afterReceiverSideMetaBehavior

public void afterReceiverSideMetaBehavior(mChaRMMethodCall msg)

it is called after the true invocation and performs meta-computation on the return value in the target locus. as default nothing it is done, it is possible to define new behavior defing a new subclass overriding this method.

Parameters:

msg - the hijacked method call.