jelly-tags/threads/src/java/org/apache/commons/jelly/tags/threads/WaitForTag.java

/*
 * Copyright 2002,2004 The Apache Software Foundation.
 *
 * 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.apache.commons.jelly.tags.threads;

import org.apache.commons.jelly.JellyTagException;
import org.apache.commons.jelly.TagSupport;
import org.apache.commons.jelly.XMLOutput;

import java.util.List;

/**
 * This tag creates a dependency on another thread. If onlyWait is set
 * a {@link TimeoutException} can be thrown. If status is set a {@link RequirementException}
 * can be thrown.
 *
 * @author <a href="mailto:jason@jhorman.org">Jason Horman</a>
 */

public class WaitForTag extends TagSupport {
    private int status = RunnableStatus.NONE;
    private JellyThread thread = null;
    private List group = null;
    private long onlyWait = -1;

    /**
     * Wait for a specific status. "SUCCESS", "FAILURE", "TIMED_OUT", or "AVOIDED". If
     * waiting on a thread group each thread in the group will have to have this status
     * set.
     */
    public void setStatus(String status) {
        this.status = RunnableStatus.getStatusCode(status);
    }

    /**
     * Which thread will this tag check the status of
     */
    public void setThread(JellyThread thread) {
        this.thread = thread;
    }

    /**
     * Set the group of threads to wait on
     */
    public void setGroup(List group) {
        this.group = group;
    }

    /**
     * Set how long to wait for the thread to finish. If waiting for a group
     * this will be the time to wait for each thread in the group to finish.
     */
    public void setOnlyWait(long onlyWait) {
        this.onlyWait = onlyWait;
    }

    /**
     * Check the requirements
     * @throws TimeoutException If the call to waitUntilDone(onlyWait) times out
     * @throws RequirementException If a threads status doesn't match the setStatus() value
     */
    public void doTag(XMLOutput output) throws TimeoutException, RequirementException, JellyTagException {
        if (thread == null && group == null) {
            throw new JellyTagException("This tag requires that you set the thread or group attribute");
        }

        // wait on the thread
        if (thread != null) {
            thread.waitUntilDone(onlyWait);
            if (status != RunnableStatus.NONE) {
                if (!thread.getStatus().equals(status)) {
                    throw new RequirementException("Requirement on thread \"" + thread.getName() + "\" not met");
                }
            }
        }

        // wait on the threadgroup
        if (group != null) {
            for (int i = 0; i < group.size(); i++) {
                JellyThread gthread = (JellyThread) group.get(i);
                gthread.waitUntilDone(onlyWait);
                if (status != RunnableStatus.NONE) {
                    if (!gthread.getStatus().equals(status)) {
                        throw new RequirementException("Requirement on thread \"" + gthread.getName() + "\" not met");
                    }
                }
            }
        }
    }
}