org.apache.tools.ant.util
Class WorkerAnt

java.lang.Object
  java.lang.Thread
      org.apache.tools.ant.util.WorkerAnt

All Implemented Interfaces:

java.lang.Runnable

public class WorkerAnt
extends java.lang.Thread

A worker ant executes a single task in a background thread. After the run, any exception thrown is turned into a buildexception, which can be rethrown, the finished attribute is set, then notifyAll() is called, so that anyone waiting on the same notify object gets woken up.

This class is effectively a superset of Parallel.TaskRunnable

Since:

Ant 1.8

Nested Class Summary

Nested classes/interfaces inherited from class java.lang.Thread

java.lang.Thread.State, java.lang.Thread.UncaughtExceptionHandler

Field Summary

static java.lang.String

ERROR_NO_TASK Error message if invoked with no task

Fields inherited from class java.lang.Thread

MAX_PRIORITY, MIN_PRIORITY, NORM_PRIORITY

Constructor Summary

WorkerAnt(Task task)
Create the worker, using the worker as the notification point.

WorkerAnt(Task task, java.lang.Object notify)
Create the worker.

Method Summary

BuildException	getBuildException() Get any build exception.
java.lang.Throwable	getException() Get whatever was thrown, which may or may not be a buildException.
Task	getTask() Get the task
boolean	isFinished() Query the task/thread for being finished.
void	rethrowAnyBuildException() Raise an exception if one was caught
void	run() Run the task, which is skipped if null.
void	waitUntilFinished(long timeout) Block on the notify object and so wait until the thread is finished.

Methods inherited from class java.lang.Thread

activeCount, checkAccess, countStackFrames, currentThread, destroy, dumpStack, enumerate, getAllStackTraces, getContextClassLoader, getDefaultUncaughtExceptionHandler, getId, getName, getPriority, getStackTrace, getState, getThreadGroup, getUncaughtExceptionHandler, holdsLock, interrupt, interrupted, isAlive, isDaemon, isInterrupted, join, join, join, resume, setContextClassLoader, setDaemon, setDefaultUncaughtExceptionHandler, setName, setPriority, setUncaughtExceptionHandler, sleep, sleep, start, stop, stop, suspend, toString, yield

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

ERROR_NO_TASK

public static final java.lang.String ERROR_NO_TASK

Error message if invoked with no task

See Also:

Constant Field Values

Constructor Detail

WorkerAnt

public WorkerAnt(Task task,
                 java.lang.Object notify)

Create the worker.

This does not start the thread, merely configures it.

Parameters:

task - the task

notify - what to notify

WorkerAnt

public WorkerAnt(Task task)

Create the worker, using the worker as the notification point.

This does not start the thread, merely configures it.

Parameters:

task - the task

Method Detail

getBuildException

public BuildException getBuildException()

Get any build exception. This would seem to be oversynchronised, but know that Java pre-1.5 can reorder volatile access. The synchronized attribute is to force an ordering.

Returns:

the exception or null

getException

public java.lang.Throwable getException()

Get whatever was thrown, which may or may not be a buildException. Assertion: getException() instanceof BuildException <=> getBuildException()==getException()

Returns:

the exception.

getTask

public Task getTask()

Get the task

Returns:

the task

isFinished

public boolean isFinished()

Query the task/thread for being finished. This would seem to be oversynchronised, but know that Java pre-1.5 can reorder volatile access. The synchronized attribute is to force an ordering.

Returns:

true if the task is finished.

waitUntilFinished

public void waitUntilFinished(long timeout)
                       throws java.lang.InterruptedException

Block on the notify object and so wait until the thread is finished.

Parameters:

timeout - timeout in milliseconds

Throws:

java.lang.InterruptedException - if the execution was interrupted

rethrowAnyBuildException

public void rethrowAnyBuildException()

Raise an exception if one was caught

Throws:

BuildException - if one has been picked up

run

public void run()

Run the task, which is skipped if null. When invoked again, the task is re-run.

Specified by:

run in interface java.lang.Runnable

Overrides:

run in class java.lang.Thread