Copyright (c) 2003, 2014 IBM Corporation and others.
 This program and the accompanying materials
 are made available under the terms of the Eclipse Public License 2.0
 which accompanies this distribution, and is available at
 https://www.eclipse.org/legal/epl-2.0/
 SPDX-License-Identifier: EPL-2.0
 Contributors:
    IBM Corporation - initial API and implementation
    Stefan Winkler - Bug 223492: Set current job name as thread name
/*******************************************************************************
 *  Copyright (c) 2003, 2014 IBM Corporation and others.
 *
 *  This program and the accompanying materials
 *  are made available under the terms of the Eclipse Public License 2.0
 *  which accompanies this distribution, and is available at
 *  https://www.eclipse.org/legal/epl-2.0/
 *
 *  SPDX-License-Identifier: EPL-2.0
 *
 *  Contributors:
 *     IBM Corporation - initial API and implementation
 *     Stefan Winkler - Bug 223492: Set current job name as thread name
 *******************************************************************************/
package org.eclipse.core.internal.jobs;

import org.eclipse.core.internal.runtime.RuntimeLog;
import org.eclipse.core.runtime.*;
import org.eclipse.core.runtime.jobs.Job;
import org.eclipse.osgi.util.NLS;

A worker thread processes jobs supplied to it by the worker pool.  When
the worker pool gives it a null job, the worker dies.
/**
 * A worker thread processes jobs supplied to it by the worker pool.  When
 * the worker pool gives it a null job, the worker dies.
 */
public class Worker extends Thread {
	// worker number used for debugging purposes only
	private static int nextWorkerNumber = 0;
	private volatile InternalJob currentJob;
	private final WorkerPool pool;
	private final String generalName;

	public Worker(WorkerPool pool) {
		super("Worker-" + nextWorkerNumber++); //$NON-NLS-1$
		this.generalName = getName();
		this.pool = pool;
		// set the context loader to avoid leaking the current context loader
		// for the thread that spawns this worker (bug 98376)
		setContextClassLoader(pool.defaultContextLoader);
	}

	
Returns the currently running job, or null if none.
/**
	 * Returns the currently running job, or null if none.
	 */
	public Job currentJob() {
		return (Job) currentJob;
	}

	private IStatus handleException(InternalJob job, Throwable t) {
		String message = NLS.bind(JobMessages.jobs_internalError, job.getName());
		return new Status(IStatus.ERROR, JobManager.PI_JOBS, JobManager.PLUGIN_ERROR, message, t);
	}

	@Override
	public void run() {
		setPriority(Thread.NORM_PRIORITY);
		try {
			while ((currentJob = pool.startJob(this)) != null) {
				IStatus result = Status.OK_STATUS;
				IProgressMonitor monitor = currentJob.getProgressMonitor();
				try {
					setName(getJobName());
					result = currentJob.run(monitor);
				} catch (OperationCanceledException e) {
					result = Status.CANCEL_STATUS;
				} catch (ThreadDeath e) {
					// must not consume thread death
					result = handleException(currentJob, e);
					throw e;
				} catch (Exception | Error e) {
					result = handleException(currentJob, e);
				} finally {
					if (result != Job.ASYNC_FINISH && monitor != null) {
						monitor.done();
					}
					// clear interrupted state for this thread
					Thread.interrupted();
					// result must not be null
					if (result == null) {
						String message = NLS.bind(JobMessages.jobs_returnNoStatus, currentJob.getClass().getName());
						result = handleException(currentJob, new NullPointerException(message));
					}
					pool.endJob(currentJob, result);
					currentJob = null;
					setName(generalName);
					// reset thread priority in case job changed it
					setPriority(Thread.NORM_PRIORITY);
				}
			}
		} catch (Throwable t) {
			RuntimeLog.log(new Status(IStatus.ERROR, JobManager.PI_JOBS, JobManager.PLUGIN_ERROR, "Unhandled error", t)); //$NON-NLS-1$
		} finally {
			currentJob = null;
			pool.endWorker(this);
		}
	}

	private String getJobName() {
		String name = currentJob.getName();
		if (name == null || name.trim().isEmpty()) {
			name = "<unnamed job: " + currentJob.getClass().getName() + ">"; //$NON-NLS-1$ //$NON-NLS-2$
		}
		return generalName + ": " + name; //$NON-NLS-1$
	}
}