package org.jgroups.protocols;
import org.jgroups.Address;
import org.jgroups.Event;
import org.jgroups.Message;
import org.jgroups.View;
import org.jgroups.annotations.MBean;
import org.jgroups.annotations.Unsupported;
import org.jgroups.stack.Protocol;
import java.io.Serializable;
import java.util.Vector;
class ExampleHeader implements Serializable {
private static final long serialVersionUID=-8802317525466899597L;
// your variables
ExampleHeader() {
}
public String toString() {
return "[EXAMPLE: <variables> ]";
}
}
/**
* Example of a protocol layer. Contains no real functionality, can be used as a template.
*/
@Unsupported
@MBean(description="Sample protocol")
public class EXAMPLE extends Protocol {
final Vector<Address> members=new Vector<Address>();
/**
* Just remove if you don't need to reset any state
*/
public static void reset() {
}
public Object up(Event evt) {
switch(evt.getType()) {
case Event.MSG:
Message msg=(Message)evt.getArg();
// Do something with the event, e.g. extract the message and remove a header.
// Optionally pass up
break;
}
return up_prot.up(evt); // Pass up to the layer above us
}
public Object down(Event evt) {
switch(evt.getType()) {
case Event.TMP_VIEW:
case Event.VIEW_CHANGE:
Vector<Address> new_members=((View)evt.getArg()).getMembers();
synchronized(members) {
members.removeAllElements();
if(new_members != null && !new_members.isEmpty())
for(int i=0; i < new_members.size(); i++)
members.addElement(new_members.elementAt(i));
}
return down_prot.down(evt);
case Event.MSG:
Message msg=(Message)evt.getArg();
// Do something with the event, e.g. add a header to the message
// Optionally pass down
break;
}
return down_prot.down(evt); // Pass on to the layer below us
}
}