org.apache.tools.ant.taskdefs
Class ExecuteWatchdog

java.lang.Object
  |
  +--org.apache.tools.ant.taskdefs.ExecuteWatchdog
All Implemented Interfaces:
TimeoutObserver

public class ExecuteWatchdog
extends java.lang.Object
implements TimeoutObserver

Destroys a process running for too long. For example:

 ExecuteWatchdog watchdog = new ExecuteWatchdog(30000);
 Execute exec = new Execute(myloghandler, watchdog);
 exec.setCommandLine(mycmdline);
 int exitvalue = exec.execute();
 if (Execute.isFailure(exitvalue) && watchdog.killedProcess()) {
              // it was killed on purpose by the watchdog
 }
 

Since:
Ant 1.2
See Also:
Execute, Watchdog

Constructor Summary
ExecuteWatchdog(int timeout)
          Deprecated. Use constructor with a long type instead. (1.4.x compatibility)
ExecuteWatchdog(long timeout)
          Creates a new watchdog with a given timeout.
 
Method Summary
 void checkException()
          This method will rethrow the exception that was possibly caught during the run of the process.
protected  void cleanUp()
          reset the monitor flag and the process.
 boolean isWatching()
          Indicates whether or not the watchdog is still monitoring the process.
 boolean killedProcess()
          Indicates whether the last process run was killed on timeout or not.
 void start(java.lang.Process process)
          Watches the given process and terminates it, if it runs for too long.
 void stop()
          Stops the watcher.
 void timeoutOccured(Watchdog w)
          Called after watchdog has finished.
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ExecuteWatchdog

public ExecuteWatchdog(long timeout)
Creates a new watchdog with a given timeout.

Parameters:
timeout - the timeout for the process in milliseconds. It must be greater than 0.

ExecuteWatchdog

public ExecuteWatchdog(int timeout)
Deprecated. Use constructor with a long type instead. (1.4.x compatibility)

See Also:
ExecuteWatchdog(long)
Method Detail

start

public void start(java.lang.Process process)
Watches the given process and terminates it, if it runs for too long. All information from the previous run are reset.

Parameters:
process - the process to monitor. It cannot be null
Throws:
java.lang.IllegalStateException - if a process is still being monitored.

stop

public void stop()
Stops the watcher. It will notify all threads possibly waiting on this object.


timeoutOccured

public void timeoutOccured(Watchdog w)
Called after watchdog has finished.

Specified by:
timeoutOccured in interface TimeoutObserver
Parameters:
w - the watchdog that timed out.

cleanUp

protected void cleanUp()
reset the monitor flag and the process.


checkException

public void checkException()
                    throws BuildException
This method will rethrow the exception that was possibly caught during the run of the process. It will only remains valid once the process has been terminated either by 'error', timeout or manual intervention. Information will be discarded once a new process is ran.

Throws:
BuildException - a wrapped exception over the one that was silently swallowed and stored during the process run.

isWatching

public boolean isWatching()
Indicates whether or not the watchdog is still monitoring the process.

Returns:
true if the process is still running, otherwise false.

killedProcess

public boolean killedProcess()
Indicates whether the last process run was killed on timeout or not.

Returns:
true if the process was killed otherwise false.


Copyright 2000-2005 Apache Software Foundation. All Rights Reserved.