org.objectweb.proactive.core.body.ft.util.faultdetection
Interface FaultDetector

All Superinterfaces:
java.rmi.Remote
All Known Implementing Classes:
GlobalFTServer

public interface FaultDetector
extends java.rmi.Remote

An object implementing this interface provides methods to detect failed active objects by sending heartbeat messages. An internal thread can be started so as to periodically test a set of active objects. This server is an RMI object.

Since:
ProActive 2.2
Author:
cdelbe

Field Summary
static int IS_DEAD
          This value is return by a dead but reachable active object that receive a heartbeat message.
static int OK
          This value is return by an alive and reachable active object that receive a heartbeat message.
 
Method Summary
 void forceDetection()
          Force a failure detection even if the failure detector thread is waiting.
 boolean isUnreachable(UniversalBody body)
          The fault detector test the reachability of the active object body by sending a heartbeat message to body.
 void startFailureDetector(LocationServer ls, RecoveryProcess rp)
          Start the tread that periodically test the reachability of objects that are registred in the location server ls.
 void stopFailureDetector()
          Stop the the failure detector thread.
 void suspendFailureDetector()
          Temporarily suspend the failure detector thread.
 

Field Detail

OK

public static final int OK
This value is return by an alive and reachable active object that receive a heartbeat message.

See Also:
Constant Field Values

IS_DEAD

public static final int IS_DEAD
This value is return by a dead but reachable active object that receive a heartbeat message.

See Also:
Constant Field Values
Method Detail

isUnreachable

public boolean isUnreachable(UniversalBody body)
                      throws java.rmi.RemoteException
The fault detector test the reachability of the active object body by sending a heartbeat message to body.

Parameters:
body - the tested active object
Returns:
true if body is unreachable, false otherwise
Throws:
java.rmi.RemoteException

startFailureDetector

public void startFailureDetector(LocationServer ls,
                                 RecoveryProcess rp)
                          throws java.rmi.RemoteException
Start the tread that periodically test the reachability of objects that are registred in the location server ls. If a failure is detected, the recovery process must be noticed.

Parameters:
ls - the location server that localizes objects to test
rp - the recovery process to notice if a failure is detected
Throws:
java.rmi.RemoteException

suspendFailureDetector

public void suspendFailureDetector()
                            throws java.rmi.RemoteException
Temporarily suspend the failure detector thread.

Throws:
java.rmi.RemoteException

stopFailureDetector

public void stopFailureDetector()
                         throws java.rmi.RemoteException
Stop the the failure detector thread.

Throws:
java.rmi.RemoteException

forceDetection

public void forceDetection()
                    throws java.rmi.RemoteException
Force a failure detection even if the failure detector thread is waiting.

Throws:
java.rmi.RemoteException


Copyright ? April 2005 INRIA All Rights Reserved.