/*
* Bitronix Transaction Manager
*
* Copyright (c) 2010, Bitronix Software.
*
* This copyrighted material is made available to anyone wishing to use, modify,
* copy, or redistribute it subject to the terms and conditions of the GNU
* Lesser General Public License, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
* or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License
* for more details.
*
* You should have received a copy of the GNU Lesser General Public License
* along with this distribution; if not, write to:
* Free Software Foundation, Inc.
* 51 Franklin Street, Fifth Floor
* Boston, MA 02110-1301 USA
*/
package bitronix.tm.twopc.executor;
import bitronix.tm.internal.BitronixRuntimeException;
import bitronix.tm.utils.ClassLoaderUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
/**
* Abstraction of the <code>java.util.concurrent</code> JDK 1.5+ implementation.
*
* @author lorban
*/
public class ConcurrentExecutor implements Executor {
private final static Logger log = LoggerFactory.getLogger(ConcurrentExecutor.class);
private final static String[] implementations = {
"java.util.concurrent.Executors",
"java.util.concurrent.ExecutorService",
"java.util.concurrent.Future",
"java.util.concurrent.TimeUnit"
};
private Object executorService;
private Method executorServiceSubmitMethod;
private Method executorServiceShutdownMethod;
private Method futureGetMethod;
private Method futureIsDoneMethod;
private Object timeUnitMilliseconds;
private boolean usable = false;
public ConcurrentExecutor() {
this(implementations);
}
protected ConcurrentExecutor(String[] implementations) {
init(implementations);
}
private void init(String[] implementations) {
String executorsImpl = implementations[0];
String executorServiceImpl = implementations[1];
String futureImpl = implementations[2];
String timeUnitImpl = implementations[3];
if (log.isDebugEnabled()) log.debug("initializing concurrent executor implementation <" + executorsImpl + ">");
try {
Class executorsClass = ClassLoaderUtils.loadClass(executorsImpl);
Class executorServiceClass = ClassLoaderUtils.loadClass(executorServiceImpl);
Class timeUnitClass = ClassLoaderUtils.loadClass(timeUnitImpl);
executorService = executorsClass.getMethod("newCachedThreadPool", (Class[]) null).invoke(executorsClass, (Object[]) null);
executorServiceSubmitMethod = executorServiceClass.getMethod("submit", new Class[] { Runnable.class });
executorServiceShutdownMethod = executorServiceClass.getMethod("shutdownNow", (Class[]) null);
timeUnitMilliseconds = timeUnitClass.getField("MILLISECONDS").get(timeUnitClass);
futureGetMethod = ClassLoaderUtils.loadClass(futureImpl).getMethod("get", new Class[] { long.class, timeUnitClass });
futureIsDoneMethod = ClassLoaderUtils.loadClass(futureImpl).getMethod("isDone", (Class[]) null);
if (log.isDebugEnabled()) log.debug("found a valid implementation for this executor <" + executorsImpl + ">");
usable = true;
} catch (Exception ex) {
if (log.isDebugEnabled()) log.debug("error accessing executor implementation <" + executorsImpl + ">", ex);
}
if (!usable)
if (log.isDebugEnabled()) log.debug("cannot find a valid implementation for executor <" + executorsImpl + ">, disabling it");
}
public Object submit(Job job) {
if (!isUsable())
throw new BitronixRuntimeException("concurrent executor is disabled because there is no valid executor implementation");
try {
return executorServiceSubmitMethod.invoke(executorService, new Object[] { job });
} catch (IllegalAccessException ex) {
throw new BitronixRuntimeException("error calling ExecutorService.submit(Runnable task)", ex);
} catch (InvocationTargetException ex) {
throw new BitronixRuntimeException("error calling ExecutorService.submit(Runnable task)", ex);
}
}
public void waitFor(Object future, long timeout) {
if (!isUsable())
throw new BitronixRuntimeException("concurrent executor is disabled because there is no valid executor implementation");
try {
futureGetMethod.invoke(future, new Object[] { new Long(timeout), timeUnitMilliseconds});
} catch (IllegalAccessException ex) {
throw new BitronixRuntimeException("error calling Future.get()", ex);
} catch (InvocationTargetException ex) {
if (ex.getCause().getClass().getName().endsWith("TimeoutException"))
return; // wait timed out, simply return
throw new BitronixRuntimeException("error calling Future.get()", ex);
}
}
public boolean isDone(Object future) {
if (!isUsable())
throw new BitronixRuntimeException("concurrent executor is disabled because there is no valid executor implementation");
try {
Boolean b = (Boolean) futureIsDoneMethod.invoke(future, (Object[]) null);
return b.booleanValue();
} catch (IllegalAccessException ex) {
throw new BitronixRuntimeException("error calling Future.isDone()", ex);
} catch (InvocationTargetException ex) {
throw new BitronixRuntimeException("error calling Future.isDone()", ex);
}
}
public boolean isUsable() {
return usable;
}
public synchronized void shutdown() {
if (!isUsable())
throw new BitronixRuntimeException("concurrent executor is disabled because there is no valid executor implementation");
try {
executorServiceShutdownMethod.invoke(executorService, (Object[]) null);
} catch (IllegalAccessException ex) {
throw new BitronixRuntimeException("error calling ExecutorService.shutdown()", ex);
} catch (InvocationTargetException ex) {
throw new BitronixRuntimeException("error calling ExecutorService.shutdown()", ex);
}
}
}