/**
* SAMOA - PROTOCOL FRAMEWORK
* Copyright (C) 2005 Olivier Rütti (EPFL) (olivier.rutti@a3.epfl.ch)
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
package seqSamoa.protocols.replacer;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.LinkedList;
import org.jdom.Element;
import seqSamoa.Message;
import seqSamoa.ProtocolModule;
import seqSamoa.ProtocolStack;
import seqSamoa.ServiceCallOrResponse;
import seqSamoa.exceptions.AlreadyBoundServiceException;
import seqSamoa.exceptions.AlreadyExistingProtocolModuleException;
import seqSamoa.exceptions.AlreadyExistingServiceException;
import seqSamoa.exceptions.SamoaClassException;
import seqSamoa.services.abcast.DynAbcast;
import seqSamoa.services.abcast.DynAbcastCallParameters;
import seqSamoa.services.abcast.DynAbcastResponseParameters;
import seqSamoa.services.replacement.ReplaceProtocol;
import seqSamoa.services.replacement.ReplaceProtocolCallParameters;
import seqSamoa.services.replacement.ReplaceProtocolResponseParameters;
import uka.transport.Transportable;
import framework.Constants;
import framework.PID;
import framework.libraries.DefaultSerialization;
import framework.libraries.serialization.TElement;
import framework.libraries.serialization.TGLinkedList;
import framework.libraries.serialization.TInteger;
import framework.libraries.serialization.TString;
/**
* This class implement a Meta-protocol for dynamic replacement of abcast
* protocol
*/
public class DynAbcastReplacer extends ProtocolModule {
final static private int MAX_MESSAGES_BUFFERED = 50;
// Service provide
private ReplaceProtocol replaceDynAbcast;
// Service required
private DynAbcast dynAbcast;
// Class for finishing the current abcast
@SuppressWarnings("serial")
public static class Terminate implements Transportable {
protected static final int _SIZE = 0;
public TString name;
public TGLinkedList<TElement> newFeatures;
public Terminate(TString name, TGLinkedList<TElement> newFeatures) {
super();
this.name = name;
this.newFeatures = newFeatures;
}
/**
* Method defined by Transportable Interface
*/
/** Used by uka.transport.UnmarshalStream to unmarshal the object */
public Terminate(uka.transport.UnmarshalStream _stream)
throws java.io.IOException, ClassNotFoundException {
this(_stream, _SIZE);
_stream.accept(_SIZE);
}
protected Terminate(uka.transport.UnmarshalStream _stream, int _size)
throws java.io.IOException, ClassNotFoundException {
_stream.request(_size);
}
/**
* Method of interface Transportable, it must be declared public. It is
* called from within UnmarshalStream after creating the object and
* assigning a stream reference to it.
*/
@SuppressWarnings("unchecked")
public void unmarshalReferences(uka.transport.UnmarshalStream _stream)
throws java.io.IOException, ClassNotFoundException {
newFeatures = (TGLinkedList<TElement>) _stream.readObject();
name = (TString) _stream.readObject();
}
/** Called directly by uka.transport.MarshalStream */
public void marshal(uka.transport.MarshalStream _stream)
throws java.io.IOException {
_stream.reserve(_SIZE);
byte[] _buffer = _stream.getBuffer();
int _pos = _stream.getPosition();
marshalPrimitives(_buffer, _pos);
_stream.deliver(_SIZE);
marshalReferences(_stream);
}
protected void marshalPrimitives(byte[] _buffer, int _pos)
throws java.io.IOException {
}
protected void marshalReferences(uka.transport.MarshalStream _stream)
throws java.io.IOException {
_stream.writeObject(newFeatures);
_stream.writeObject(name);
}
public final Object deepClone(uka.transport.DeepClone _helper)
throws CloneNotSupportedException {
Object _copy = clone();
_helper.add(this, _copy);
((Terminate) _copy).deepCloneReferences(_helper);
return _copy;
}
/**
* Clone all references to other objects. Use the DeepClone to resolve
* cycles
*/
@SuppressWarnings("unchecked")
protected void deepCloneReferences(uka.transport.DeepClone _helper)
throws CloneNotSupportedException {
this.newFeatures = (TGLinkedList<TElement>) _helper
.doDeepClone(this.newFeatures);
this.name = (TString) _helper.doDeepClone(this.name);
}
}
@SuppressWarnings("serial")
public static class SequencedMessage implements Transportable {
protected static final int _SIZE = 0;
private Transportable content;
private TInteger seqNumber;
public SequencedMessage(Transportable content, TInteger seqNumber) {
super();
this.content = content;
this.seqNumber = seqNumber;
}
public boolean equals(Object obj) {
return ((obj instanceof SequencedMessage)
&& ((SequencedMessage) obj).content.equals(this.content) && ((SequencedMessage) obj).seqNumber
.equals(this.seqNumber));
}
/**
* Method defined by Transportable Interface
*/
/** Used by uka.transport.UnmarshalStream to unmarshal the object */
public SequencedMessage(uka.transport.UnmarshalStream _stream)
throws java.io.IOException, ClassNotFoundException {
this(_stream, _SIZE);
_stream.accept(_SIZE);
}
protected SequencedMessage(uka.transport.UnmarshalStream _stream,
int _size) throws java.io.IOException, ClassNotFoundException {
_stream.request(_size);
}
/**
* Method of interface Transportable, it must be declared public. It is
* called from within UnmarshalStream after creating the object and
* assigning a stream reference to it.
*/
public void unmarshalReferences(uka.transport.UnmarshalStream _stream)
throws java.io.IOException, ClassNotFoundException {
content = (Transportable) _stream.readObject();
seqNumber = (TInteger) _stream.readObject();
}
/** Called directly by uka.transport.MarshalStream */
public void marshal(uka.transport.MarshalStream _stream)
throws java.io.IOException {
_stream.reserve(_SIZE);
byte[] _buffer = _stream.getBuffer();
int _pos = _stream.getPosition();
marshalPrimitives(_buffer, _pos);
_stream.deliver(_SIZE);
marshalReferences(_stream);
}
protected void marshalPrimitives(byte[] _buffer, int _pos)
throws java.io.IOException {
}
protected void marshalReferences(uka.transport.MarshalStream _stream)
throws java.io.IOException {
_stream.writeObject(content);
_stream.writeObject(seqNumber);
}
public final Object deepClone(uka.transport.DeepClone _helper)
throws CloneNotSupportedException {
Object _copy = clone();
_helper.add(this, _copy);
((SequencedMessage) _copy).deepCloneReferences(_helper);
return _copy;
}
/**
* Clone all references to other objects. Use the DeepClone to resolve
* cycles
*/
protected void deepCloneReferences(uka.transport.DeepClone _helper)
throws CloneNotSupportedException {
this.content = (Transportable) _helper.doDeepClone(this.content);
this.seqNumber = (TInteger) _helper.doDeepClone(this.seqNumber);
}
}
// The current ID of the Abcast protocol
protected int sendSeqNumber;
protected int recvSeqNumber;
// The list of messages undelivered and abcasted locally
protected ArrayList<Message> undeliveredMessages;
protected ArrayList<TInteger> undeliveredType;
protected ArrayList<PID> undeliveredPID;
// The list of messages delivered by an abcast protocol not yet bound
protected ArrayList<Message> bufferized;
// The Executer
protected ReplaceProtocol.Executer replaceDynAbcastExecuter;
// The Interceptor
// It listen to DynABCAST calls and responses
protected DynAbcast.Interceptor dynAbcastInterceptor;
/**
* Constructor. <br>
*
* @param name
* Name of the layer
* @param stack
* The stack in which the module will be
*/
public DynAbcastReplacer(String name, ProtocolStack stack,
ReplaceProtocol replaceProtocol, DynAbcast dynAb) throws AlreadyExistingProtocolModuleException {
super(name, stack);
this.replaceDynAbcast = replaceProtocol;
this.dynAbcast = dynAb;
// Init the current abcast and some data
sendSeqNumber = 0;
recvSeqNumber = 0;
undeliveredMessages = new ArrayList<Message>();
undeliveredType = new ArrayList<TInteger>();
undeliveredPID = new ArrayList<PID>();
bufferized = new ArrayList<Message>();
LinkedList<ServiceCallOrResponse> initiatedReplace = new LinkedList<ServiceCallOrResponse>();
initiatedReplace.add(ServiceCallOrResponse.createServiceCallOrResponse(dynAbcast, true));
replaceDynAbcastExecuter = replaceDynAbcast.new Executer(this, initiatedReplace) {
public void evaluate(ReplaceProtocolCallParameters infos,
Message dmessage) {
synchronized (this.parent) {
Terminate term = new Terminate(infos.name, infos.newFeatures);
SequencedMessage seqMessage = new SequencedMessage(term,
new TInteger(sendSeqNumber));
Message dmes = new Message(seqMessage, null);
TInteger atype = new TInteger(Constants.AM);
DynAbcastCallParameters aparams = new DynAbcastCallParameters(
atype, null);
// SEND THE TERMINATE MESSAGE TO ALL
dynAbcastInterceptor.forwardCall(aparams, dmes);
// GET THE NEW PROTOCOL
createFeatures(term.name.toString(), term.newFeatures);
sendSeqNumber++;
}
}
};
LinkedList<ServiceCallOrResponse> initiatedAbcast = new LinkedList<ServiceCallOrResponse>();
for (int i=0; i<MAX_MESSAGES_BUFFERED; i++)
initiatedAbcast.add(ServiceCallOrResponse.createServiceCallOrResponse(dynAbcast, true));
initiatedAbcast.add(ServiceCallOrResponse.createServiceCallOrResponse(replaceDynAbcast, false));
dynAbcastInterceptor = dynAbcast.new Interceptor(this, initiatedAbcast) {
public void interceptCall(DynAbcastCallParameters params,
Message dmessage) {
synchronized (this.parent) {
try {
dmessage.content = new SequencedMessage(
dmessage.content, new TInteger(sendSeqNumber));
undeliveredMessages.add((Message) deepClone(dmessage));
undeliveredType.add(params.type);
undeliveredPID.add(params.pid);
forwardCall(params, dmessage);
} catch (ClassNotFoundException ex) {
throw new RuntimeException(
"Can not abcast this message!");
} catch (IOException ex) {
ex.printStackTrace();
throw new RuntimeException(
"Can not abcast this message!"
+ ex.getMessage());
}
}
}
public void interceptResponse(DynAbcastResponseParameters infos,
Message dmessage) {
synchronized (this.parent) {
SequencedMessage seqMessage = (SequencedMessage) dmessage.content;
if (seqMessage.seqNumber.intValue() == recvSeqNumber) {
// We can deliver this message
if (seqMessage.content instanceof Terminate) {
// Terminate message -> switch protocol
Terminate term = (Terminate) seqMessage.content;
// Increase seqNumber and
// create the new protocol if necessary
recvSeqNumber++;
if (sendSeqNumber < recvSeqNumber) {
// Create the new protocol
sendSeqNumber++;
createFeatures(term.name.toString(), term.newFeatures);
}
// Deliver messages in bufferized
int pointer = 0;
while (bufferized.size() > 0
&& pointer < bufferized.size()) {
Message dmessageTmp = bufferized.get(pointer);
SequencedMessage seqMessageTmp = (SequencedMessage) dmessageTmp.content;
if (seqMessageTmp.seqNumber.intValue() == recvSeqNumber) {
removeFromUndelivered(seqMessageTmp);
dmessageTmp.content = seqMessageTmp.content;
forwardResponse(infos, dmessageTmp);
bufferized.remove(pointer);
} else
pointer++;
}
// Send Messages in Undelivered again
int undeliveredSize = undeliveredMessages.size();
for (int i = 0; i < undeliveredSize; i++) {
Message dmessageTmp = undeliveredMessages
.get(i);
SequencedMessage seqMessageTmp = (SequencedMessage) dmessageTmp.content;
if (seqMessageTmp.seqNumber.intValue() < sendSeqNumber) {
DynAbcastCallParameters params = new DynAbcastCallParameters(
undeliveredType.get(i),
undeliveredPID.get(i));
seqMessageTmp.seqNumber = new TInteger(
sendSeqNumber);
try {
forwardCall(
params,
(Message) deepClone(dmessageTmp));
} catch (ClassNotFoundException ex) {
throw new RuntimeException(
"Can not abcast "
+ "this message!");
} catch (IOException ex) {
throw new RuntimeException(
"Can not abcast "
+ "this message!");
}
}
}
} else {
// Normal Abcast message
removeFromUndelivered(seqMessage);
dmessage.content = seqMessage.content;
forwardResponse(infos, dmessage);
}
} else if (seqMessage.seqNumber.intValue() > recvSeqNumber) {
// This message should be delivered later
bufferized.add(dmessage);
removeFromUndelivered(seqMessage);
}
}
}
};
}
// Remove the message from undelivered
private void removeFromUndelivered(SequencedMessage message) {
int undelSize = undeliveredMessages.size();
for (int i = 0; i < undelSize; i++) {
try {
if (message.equals(undeliveredMessages.get(i).content)) {
undeliveredMessages.remove(i);
undeliveredType.remove(i);
undeliveredPID.remove(i);
return;
}
} catch (IndexOutOfBoundsException ex) {
throw new RuntimeException("There is some bug!!!!");
}
}
}
// Add all the protocols and services of the list in the stack
private void createFeatures(String name, TGLinkedList<TElement> newFeatures) {
Iterator<TElement> it = newFeatures.iterator();
while (it.hasNext()) {
Element element = it.next().getElement();
try {
if (element.getName().equals("Service")) {
this.stack.newService(element);
} else if (element.getName().equals("Protocol")) {
ProtocolModule newProt = this.stack.newProtocolModule(element);
newProt.init();
if (!newProt.getName().equals(name))
newProt.linkToService();
} else
throw new RuntimeException("Unknown Element Name: " + element);
} catch (SamoaClassException e) {
System.err.println(e.getMessage());
} catch (AlreadyExistingServiceException e) {
System.err.println("Service already exist: "+element.getChildText("Name"));
} catch (AlreadyExistingProtocolModuleException e) {
System.err.println("Protocol already exist: "+element.getChildText("Name"));
} catch (AlreadyBoundServiceException e) {
System.err.println("Service provided by the protocol has already a provider: "+element.getChildText("Name"));
}
}
// Unlink the old protocol and bound the new one
try {
ProtocolModule newP = stack.getProtocol(name);
if (newP != null) {
dynAbcast.unlinkExecuter();
newP.linkToService();
// Issue a response informing of the change of protocol
ReplaceProtocolResponseParameters nparams = new ReplaceProtocolResponseParameters(
dynAbcast, newP);
replaceDynAbcast.response(nparams, null);
} else
System.err.println("The protocol with name "+name+" does not exist!");
} catch (AlreadyBoundServiceException ex) {
throw new RuntimeException("Error in conception. Should not be possible!");
}
}
// Makes a complete deep copy of the parameter o
private Transportable deepClone(Transportable o) throws IOException,
ClassNotFoundException {
// TODO: There have to be better ways to do deep-clone!!!
return DefaultSerialization
.unmarshall(DefaultSerialization.marshall(o));
}
}