/* WatchDog timer for tests

 @Copyright (c) 2003-2010 The Regents of the University of California.
 All rights reserved.

 Permission is hereby granted, without written agreement and without
 license or royalty fees, to use, copy, modify, and distribute this
 software and its documentation for any purpose, provided that the
 above copyright notice and the following two paragraphs appear in all
 copies of this software.

 IN NO EVENT SHALL THE UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY
 FOR DIRECT, INDIRECT, SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES
 ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
 THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
 SUCH DAMAGE.

 THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY WARRANTIES,
 INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
 PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
 CALIFORNIA HAS NO OBLIGATION TO PROVIDE MAINTENANCE, SUPPORT, UPDATES,
 ENHANCEMENTS, OR MODIFICATIONS.

 PT_COPYRIGHT_VERSION_2
 COPYRIGHTENDKEY

 */
package util.testsuite;

import java.util.Date;
import java.util.Timer;
import java.util.TimerTask;

import ptolemy.util.StringUtilities;

//////////////////////////////////////////////////////////////////////////
//// WatchDog

/** This class creates a Timer that calls System.exit() after
 a certain amount of time.

 @author Christopher Hylands
 @version $Id: WatchDog.java 57046 2010-01-27 23:35:53Z cxh $
 @since Ptolemy II 2.2
 @Pt.ProposedRating Red (cxh)
 @Pt.AcceptedRating Red (cxh)
 */
public class WatchDog {
    /** Create a timer that will go off after timeToDie milliseconds.
     *  @param timeToDie The time in millesconds when the timer will
     *  go off.
     */
    public WatchDog(final long timeToDie) {
        // Timers are new in JDK1.3
        // For information about Timers, see
        // http://java.sun.com/docs/books/tutorial/essential/threads/timer.html
        if (timeToDie <= 0) {
            return;
        }

        TimerTask doTimeToDie = new TimerTask() {
            public void run() {
                try {
                    System.err.println("*** util.testsuite.WatchDog went "
                            + "off after " + timeToDie + "ms. "
                            + new Date().toString());

                    // Get the root ThreadGroup
                    ThreadGroup parent;

                    // Get the root ThreadGroup
                    ThreadGroup rootGroup;

                    parent = Thread.currentThread().getThreadGroup();

                    do {
                        rootGroup = parent;
                        parent = parent.getParent();
                    } while (parent != null);

                    // Display all the threads
                    Thread[] threads = new Thread[rootGroup.activeCount()];
                    rootGroup.enumerate(threads);

                    for (int i = 0; i < threads.length; i++) {
                        System.err.println(i + ". " + threads[i]);

                        // It would be nice to display the stack traces,
                        // but this is hard to do.  Thread.dumpStack()
                        // only dumps the stack trace for the current thread.
                        // For an idea using Thread.stop(), see
                        // http://forum.java.sun.com/thread.jsp?forum=4&thread=178641&start=15&range=15&hilite=false&q=
                    }
                } catch (Exception e) {
                    System.err.println(e);
                } finally {
                    System.out.println("util.testsuite.WatchDog went off");
                    watchDogWentOff = true;

                    if (_exitOnTimeOut) {
                        String userDir = "util.testsuite.WatchDog went off";
                        try {
                            userDir = System.getProperty("user.dir");
                        } catch (Exception ex) {
                            // ignore
                        }
                        System.out.println("The string below is so that "
                                + "the nightly build will notice\n"
                                + "Failed: 666  Total Tests: 0 "
                                + "((Passed: 0, Newly Passed: 0)  "
                                + "Known Failed: 0) " + userDir);

                        // Do not pass go, do not collect $200
                        StringUtilities.exit(4);
                    }
                }
            }
        };

        if (_timer == null) {
            // Create the timer as a Daemon.. This way it won't prevent
            // the compiler from exiting if an exception occurs.
            _timer = new Timer(true);
        }

        _timer.schedule(doTimeToDie, timeToDie);
    }

    /** Cancel the currently pending watchdog.
     */
    public void cancel() {
        System.out.println("util.testsuite.WatchDog.cancel(): canceling "
                + (new Date()));

        if (_timer == null) {
            System.out.println("util.testsuite.WatchDog.cancel(): "
                    + "Warning: cancel called twice?");
        } else {
            _timer.cancel();
            _timer = null;
        }
    }

    /** Determine whether the JVM will exit when the time interval
     *  has passed.  This method is used for testing this class.
     *  @param exitOnTimeOut True if the JVM will exit when
     *  the time interval has passed.
     */
    public void setExitOnTimeOut(boolean exitOnTimeOut) {
        _exitOnTimeOut = exitOnTimeOut;
    }

    /** Set to true if the watch time timer interval has passed.
     *  Used primarily for testing.
     */
    public boolean watchDogWentOff = false;

    private Timer _timer = null;

    // If true, then exit if the interval passes
    private boolean _exitOnTimeOut = true;
}