/*
* Copyright 2002-2008 the original author or authors.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.springframework.scheduling.commonj;
import java.util.Collection;
import javax.naming.NamingException;
import commonj.work.Work;
import commonj.work.WorkException;
import commonj.work.WorkItem;
import commonj.work.WorkListener;
import commonj.work.WorkManager;
import commonj.work.WorkRejectedException;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.task.TaskRejectedException;
import org.springframework.jndi.JndiLocatorSupport;
import org.springframework.scheduling.SchedulingException;
import org.springframework.scheduling.SchedulingTaskExecutor;
import org.springframework.util.Assert;
/**
* TaskExecutor implementation that delegates to a CommonJ WorkManager,
* implementing the {@link commonj.work.WorkManager} interface,
* which either needs to be specified as reference or through the JNDI name.
*
* <p><b>This is the central convenience class for setting up a
* CommonJ WorkManager in a Spring context.</b>
*
* <p>Also implements the CommonJ WorkManager interface itself, delegating all
* calls to the target WorkManager. Hence, a caller can choose whether it wants
* to talk to this executor through the Spring TaskExecutor interface or the
* CommonJ WorkManager interface.
*
* <p>The CommonJ WorkManager will usually be retrieved from the application
* server's JNDI environment, as defined in the server's management console.
*
* <p><b>Note: At the time of this writing, the CommonJ WorkManager facility
* is only supported on IBM WebSphere 6.0+ and BEA WebLogic 9.0+,
* despite being such a crucial API for an application server.</b>
* (There is a similar facility available on WebSphere 5.1 Enterprise,
* though, which we will discuss below.)
*
* <p><b>On JBoss and GlassFish, a similar facility is available through
* the JCA WorkManager.</b> See the
* {@link org.springframework.jca.work.jboss.JBossWorkManagerTaskExecutor}
* {@link org.springframework.jca.work.glassfish.GlassFishWorkManagerTaskExecutor}
* classes which are the direct equivalent of this CommonJ adapter class.
*
* <p>A similar facility is available on WebSphere 5.1, under the name
* "Asynch Beans". Its central interface is called WorkManager too and is
* also obtained from JNDI, just like a standard CommonJ WorkManager.
* However, this WorkManager variant is notably different: The central
* execution method is called "startWork" instead of "schedule",
* and takes a slightly different Work interface as parameter.
*
* <p>Support for this WebSphere 5.1 variant can be built with this class
* and its helper DelegatingWork as template: Call the WorkManager's
* <code>startWork(Work)</code> instead of <code>schedule(Work)</code>
* in the <code>execute(Runnable)</code> implementation. Furthermore,
* for simplicity's sake, drop the entire "Implementation of the CommonJ
* WorkManager interface" section (and the corresponding
* <code>implements WorkManager</code> clause at the class level).
* Of course, you also need to change all <code>commonj.work</code> imports in
* your WorkManagerTaskExecutor and DelegatingWork variants to the corresponding
* WebSphere API imports (<code>com.ibm.websphere.asynchbeans.WorkManager</code>
* and <code>com.ibm.websphere.asynchbeans.Work</code>, respectively).
* This should be sufficient to get a TaskExecutor adapter for WebSphere 5.
*
* @author Juergen Hoeller
* @since 2.0
*/
public class WorkManagerTaskExecutor extends JndiLocatorSupport
implements SchedulingTaskExecutor, WorkManager, InitializingBean {
private WorkManager workManager;
private String workManagerName;
private WorkListener workListener;
/**
* Specify the CommonJ WorkManager to delegate to.
* <p>Alternatively, you can also specify the JNDI name
* of the target WorkManager.
* @see #setWorkManagerName
*/
public void setWorkManager(WorkManager workManager) {
this.workManager = workManager;
}
/**
* Set the JNDI name of the CommonJ WorkManager.
* <p>This can either be a fully qualified JNDI name,
* or the JNDI name relative to the current environment
* naming context if "resourceRef" is set to "true".
* @see #setWorkManager
* @see #setResourceRef
*/
public void setWorkManagerName(String workManagerName) {
this.workManagerName = workManagerName;
}
/**
* Specify a CommonJ WorkListener to apply, if any.
* <p>This shared WorkListener instance will be passed on to the
* WorkManager by all {@link #execute} calls on this TaskExecutor.
*/
public void setWorkListener(WorkListener workListener) {
this.workListener = workListener;
}
public void afterPropertiesSet() throws NamingException {
if (this.workManager == null) {
if (this.workManagerName == null) {
throw new IllegalArgumentException("Either 'workManager' or 'workManagerName' must be specified");
}
this.workManager = (WorkManager) lookup(this.workManagerName, WorkManager.class);
}
}
//-------------------------------------------------------------------------
// Implementation of the Spring SchedulingTaskExecutor interface
//-------------------------------------------------------------------------
public void execute(Runnable task) {
Assert.state(this.workManager != null, "No WorkManager specified");
Work work = new DelegatingWork(task);
try {
if (this.workListener != null) {
this.workManager.schedule(work, this.workListener);
}
else {
this.workManager.schedule(work);
}
}
catch (WorkRejectedException ex) {
throw new TaskRejectedException("CommonJ WorkManager did not accept task: " + task, ex);
}
catch (WorkException ex) {
throw new SchedulingException("Could not schedule task on CommonJ WorkManager", ex);
}
}
/**
* This task executor prefers short-lived work units.
*/
public boolean prefersShortLivedTasks() {
return true;
}
//-------------------------------------------------------------------------
// Implementation of the CommonJ WorkManager interface
//-------------------------------------------------------------------------
public WorkItem schedule(Work work)
throws WorkException, IllegalArgumentException {
return this.workManager.schedule(work);
}
public WorkItem schedule(Work work, WorkListener workListener)
throws WorkException, IllegalArgumentException {
return this.workManager.schedule(work, workListener);
}
public boolean waitForAll(Collection workItems, long timeout)
throws InterruptedException, IllegalArgumentException {
return this.workManager.waitForAll(workItems, timeout);
}
public Collection waitForAny(Collection workItems, long timeout)
throws InterruptedException, IllegalArgumentException {
return this.workManager.waitForAny(workItems, timeout);
}
}