/**
* Copyright 2013 JogAmp Community. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are
* permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice, this list of
* conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright notice, this list
* of conditions and the following disclaimer in the documentation and/or other materials
* provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
* FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR
* CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
* SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON
* ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*
* The views and conclusions contained in the software and documentation are those of the
* authors and should not be interpreted as representing official policies, either expressed
* or implied, of JogAmp Community.
*/
package com.jogamp.common.util;
import java.io.PrintStream;
import com.jogamp.common.JogampRuntimeException;
/**
* Helper class to provide a Runnable queue implementation with a Runnable wrapper
* which notifies after execution for the <code>invokeAndWait()</code> semantics.
*/
public class FunctionTask<R,A> extends TaskBase implements Function<R,A> {
protected Function<R,A> runnable;
protected R result;
protected A[] args;
/**
* Invokes <code>func</code> on the current {@link Thread}.
* <p>
* The result can be retrieved via {@link FunctionTask#getResult()},
* using the returned instance.
* </p>
* @param func the {@link Function} to execute.
* @param args the {@link Function} arguments
* @return the newly created and invoked {@link FunctionTask}
* @since 2.4.0
*/
public static <U,V> FunctionTask<U,V> invokeOnCurrentThread(final Function<U,V> func, final V... args) {
final FunctionTask<U,V> rt = new FunctionTask<U,V>( func, null, false, null);
rt.args = args;
rt.run();
return rt;
}
/**
* Invokes <code>func</code> on a new {@link InterruptSource.Thread},
* see {@link InterruptSource.Thread#Thread(ThreadGroup, Runnable, String)} for details.
* <p>
* The result can be retrieved via {@link FunctionTask#getResult()},
* using the returned instance.
* </p>
* @param tg the {@link ThreadGroup} for the new thread, maybe <code>null</code>
* @param threadName the name for the new thread, maybe <code>null</code>
* @param waitUntilDone if <code>true</code>, waits until <code>func</code> execution is completed, otherwise returns immediately.
* @param func the {@link Function} to execute.
* @param args the {@link Function} arguments
* @return the newly created and invoked {@link FunctionTask}
* @since 2.3.2
*/
public static <U,V> FunctionTask<U,V> invokeOnNewThread(final ThreadGroup tg, final String threadName,
final boolean waitUntilDone, final Function<U,V> func, final V... args) {
final FunctionTask<U,V> rt;
if( !waitUntilDone ) {
rt = new FunctionTask<U,V>( func, null, true, System.err );
final InterruptSource.Thread t = InterruptSource.Thread.create(tg, rt, threadName);
rt.args = args;
t.start();
} else {
final Object sync = new Object();
rt = new FunctionTask<U,V>( func, sync, true, null );
final InterruptSource.Thread t = InterruptSource.Thread.create(tg, rt, threadName);
synchronized(sync) {
rt.args = args;
t.start();
while( rt.isInQueue() ) {
try {
sync.wait();
} catch (final InterruptedException ie) {
throw new InterruptedRuntimeException(ie);
}
final Throwable throwable = rt.getThrowable();
if(null!=throwable) {
throw new JogampRuntimeException(throwable);
}
}
}
}
return rt;
}
/**
* Create a RunnableTask object w/ synchronization,
* ie. suitable for <code>invokeAndWait()</code>.
*
* @param runnable the user action
* @param syncObject the synchronization object the caller shall wait until <code>runnable</code> execution is completed,
* or <code>null</code> if waiting is not desired.
* @param catchExceptions Influence an occurring exception during <code>runnable</code> execution.
* If <code>true</code>, the exception is silenced and can be retrieved via {@link #getThrowable()},
* otherwise the exception is thrown.
* @param exceptionOut If not <code>null</code>, exceptions are written to this {@link PrintStream}.
*/
public FunctionTask(final Function<R,A> runnable, final Object syncObject, final boolean catchExceptions, final PrintStream exceptionOut) {
super(syncObject, catchExceptions, exceptionOut);
this.runnable = runnable ;
result = null;
args = null;
}
/** Return the user action */
public final Function<R,A> getRunnable() {
return runnable;
}
/**
* Sets the arguments for {@link #run()}.
* They will be cleared after calling {@link #run()} or {@link #eval(Object...)}.
*/
public final void setArgs(final A... args) {
this.args = args;
}
/**
* Retrieves the cached result of {@link #run()}
* and is cleared within this method.
*/
public final R getResult() {
final R res = result;
result = null;
return res;
}
/**
* {@inheritDoc}
* <p>
* Calls {@link #eval(Object...)}.
* </p>
* <p>
* You may set the {@link #eval(Object...)} arguments via {@link #setArgs(Object...)}
* and retrieve the result via {@link #getResult()}.
* </p>
*/
@Override
public final void run() {
execThread = Thread.currentThread();
final A[] args = this.args;
this.args = null;
this.result = null;
runnableException = null;
tStarted = System.currentTimeMillis();
if(null == syncObject) {
try {
this.result = runnable.eval(args);
} catch (final Throwable t) {
runnableException = t;
if(null != exceptionOut) {
exceptionOut.println("FunctionTask.run(): "+getExceptionOutIntro()+" exception occured on thread "+Thread.currentThread().getName()+": "+toString());
printSourceTrace();
t.printStackTrace(exceptionOut);
}
if(!catchExceptions) {
throw new RuntimeException(runnableException);
}
} finally {
tExecuted = System.currentTimeMillis();
isExecuted = true;
}
} else {
synchronized (syncObject) {
try {
this.result = runnable.eval(args);
} catch (final Throwable t) {
runnableException = t;
if(null != exceptionOut) {
exceptionOut.println("FunctionTask.run(): "+getExceptionOutIntro()+" exception occured on thread "+Thread.currentThread().getName()+": "+toString());
printSourceTrace();
t.printStackTrace(exceptionOut);
}
if(!catchExceptions) {
throw new RuntimeException(runnableException);
}
} finally {
tExecuted = System.currentTimeMillis();
isExecuted = true;
syncObject.notifyAll();
}
}
}
}
@Override
public final R eval(final A... args) {
this.args = args;
run();
final R res = result;
result = null;
return res;
}
}