taverna-server-worker/src/main/java/org/taverna/server/localworker/impl/utils/TimingOutTask.java

package org.taverna.server.localworker.impl.utils;
/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You 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.
 */

import javax.annotation.Nullable;

/**
 * A class that handles running a task that can take some time.
 * 
 * @author Donal Fellows
 * 
 */
public abstract class TimingOutTask extends Thread {
	public abstract void doIt() throws Exception;

	@Nullable
	private Exception ioe;

	@Override
	public final void run() {
		try {
			doIt();
		} catch (Exception ioe) {
			this.ioe = ioe;
		}
	}

	public TimingOutTask() {
		this.setDaemon(true);
	}

	public void doOrTimeOut(long timeout) throws Exception {
		start();
		try {
			join(timeout);
		} catch (InterruptedException e) {
			interrupt();
		}
		if (ioe != null)
			throw ioe;
	}
}