/*****************************************************************
JADE - Java Agent DEvelopment Framework is a framework to develop
multi-agent systems in compliance with the FIPA specifications.
Copyright (C) 2000 CSELT S.p.A.
GNU Lesser General Public License
This library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation,
version 2.1 of the License.
This library 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
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with this library; if not, write to the
Free Software Foundation, Inc., 59 Temple Place - Suite 330,
Boston, MA 02111-1307, USA.
*****************************************************************/
package jade.core;
import jade.util.leap.Iterator;
import jade.util.leap.EnumIterator;
import jade.util.leap.List;
import jade.util.leap.LinkedList;
import java.util.Vector;
import jade.lang.acl.ACLMessage;
import jade.lang.acl.MessageTemplate;
/**
@author Giovanni Rimassa - Universita` di Parma
@version $Date: 2006-01-12 13:21:47 +0100 (gio, 12 gen 2006) $ $Revision: 5847 $
*/
class InternalMessageQueue implements MessageQueue {
//#MIDP_EXCLUDE_BEGIN
// In MIDP we use Vector instead of jade.util.leap.LinkedList as the latter has been implemented in terms of the first
private LinkedList list;
//#MIDP_EXCLUDE_END
/*#MIDP_INCLUDE_BEGIN
private Vector list;
#MIDP_INCLUDE_END*/
private int maxSize;
public InternalMessageQueue(int size) {
maxSize = size;
//#MIDP_EXCLUDE_BEGIN
list = new LinkedList();
//#MIDP_EXCLUDE_END
/*#MIDP_INCLUDE_BEGIN
list = new Vector();
#MIDP_INCLUDE_END*/
}
public InternalMessageQueue() {
this(0);
}
public boolean isEmpty() {
return list.isEmpty();
}
public void setMaxSize(int newSize) throws IllegalArgumentException {
if(newSize < 0)
throw new IllegalArgumentException("Invalid MsgQueue size");
maxSize = newSize;
}
public int getMaxSize() {
return maxSize;
}
/**
* @return the number of messages
* currently in the queue
**/
public int size() {
return list.size();
}
public void addFirst(ACLMessage msg) {
if((maxSize != 0) && (list.size() >= maxSize)) {
//#MIDP_EXCLUDE_BEGIN
list.removeFirst(); // FIFO replacement policy
}
list.addFirst(msg);
//#MIDP_EXCLUDE_END
/*#MIDP_INCLUDE_BEGIN
list.setElementAt(msg,0);
} else
list.insertElementAt(msg,0);
#MIDP_INCLUDE_END*/
}
public void addLast(ACLMessage msg) {
if((maxSize != 0) && (list.size() >= maxSize)){
//#MIDP_EXCLUDE_BEGIN
list.removeFirst(); // FIFO replacement policy
System.err.println("WARNING: a message has been lost by an agent because of the FIFO replacement policy of its message queue.\n Notice that, under some circumstances, this might not be the proper expected behaviour and the size of the queue needs to be increased. Check the method Agent.setQueueSize()");
}
list.addLast(msg);
//#MIDP_EXCLUDE_END
/*#MIDP_INCLUDE_BEGIN
list.removeElementAt(0);
}
list.addElement(msg);
#MIDP_INCLUDE_END*/
}
public ACLMessage receive(MessageTemplate pattern) {
ACLMessage result = null;
// This is just for the MIDP implementation where iterator.remove() is not supported.
// We don't surround it with preprocessor directives to avoid making the code unreadable
int cnt = 0;
for (Iterator messages = iterator(); messages.hasNext(); cnt++) {
ACLMessage msg = (ACLMessage)messages.next();
if (pattern == null || pattern.match(msg)) {
//#MIDP_EXCLUDE_BEGIN
messages.remove();
//#MIDP_EXCLUDE_END
/*#MIDP_INCLUDE_BEGIN
list.removeElementAt(cnt);
#MIDP_INCLUDE_END*/
result = msg;
break;
}
}
return result;
}
private Iterator iterator() {
//#MIDP_EXCLUDE_BEGIN
return list.iterator();
//#MIDP_EXCLUDE_END
/*#MIDP_INCLUDE_BEGIN
return new EnumIterator(list.elements());
#MIDP_INCLUDE_END*/
}
//#J2ME_EXCLUDE_BEGIN
// For persistence service
private void setMessages(java.util.List l) {
// FIXME: To be implemented
System.out.println(">>> MessageQueue::setMessages() <<<");
}
// For persistence service
private java.util.List getMessages() {
// FIXME: To be implemented
System.out.println(">>> MessageQueue::getMessages() <<<");
return null;
}
//#J2ME_EXCLUDE_END
// For persistence service
private Long persistentID;
// For persistence service
private Long getPersistentID() {
return persistentID;
}
// For persistence service
private void setPersistentID(Long l) {
persistentID = l;
}
//#MIDP_EXCLUDE_BEGIN
public void copyTo(List messages) {
for (Iterator i = iterator(); i.hasNext(); messages.add(i.next()));
}
// For debugging purpose
Object[] getAllMessages() {
return list.toArray();
}
//#MIDP_EXCLUDE_END
}