package org.jgroups.blocks.mux;
import java.util.Map;
import java.util.concurrent.ConcurrentHashMap;
import org.jgroups.Event;
import org.jgroups.Message;
import org.jgroups.UpHandler;
/**
* Allows up handler multiplexing.
*
* @author Bela Ban
* @author Paul Ferraro
* @version $Id: MuxUpHandler.java,v 1.2 2010/04/15 20:05:22 ferraro Exp $
*/
public class MuxUpHandler implements UpHandler, Muxer<UpHandler> {
private final Map<Short, UpHandler> handlers = new ConcurrentHashMap<Short, UpHandler>();
private final UpHandler defaultHandler;
/**
* Creates a multiplexing up handler, with no default handler.
*/
public MuxUpHandler() {
this.defaultHandler = null;
}
/**
* Creates a multiplexing up handler using the specified default handler.
* @param defaultHandler a default up handler to handle messages with no {@link MuxHeader}
*/
public MuxUpHandler(UpHandler defaultHandler) {
this.defaultHandler = defaultHandler;
}
/**
* {@inheritDoc}
* @see org.jgroups.blocks.mux.Muxer#add(short, java.lang.Object)
*/
@Override
public void add(short id, UpHandler handler) {
handlers.put(id, handler);
}
/**
* {@inheritDoc}
* @see org.jgroups.blocks.mux.Muxer#remove(short)
*/
@Override
public void remove(short id) {
handlers.remove(id);
}
/**
* {@inheritDoc}
* @see org.jgroups.UpHandler#up(org.jgroups.Event)
*/
@Override
public Object up(Event evt) {
switch (evt.getType()) {
case Event.MSG: {
Message msg = (Message) evt.getArg();
MuxHeader hdr = (MuxHeader) msg.getHeader(MuxRequestCorrelator.MUX_ID);
if (hdr != null) {
short id = hdr.getId();
UpHandler handler = handlers.get(id);
return (handler != null) ? handler.up(evt) : new NoMuxHandler(id);
}
break;
}
case Event.VIEW_CHANGE: {
for (UpHandler handler: handlers.values()) {
handler.up(evt);
}
break;
}
}
return (defaultHandler != null) ? defaultHandler.up(evt) : null;
}
}