PeriodicNode.java

package com.roboclub.robobuggy.nodes.baseNodes;

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

/**
 * This node will cause for an update function to be run at a fixed frequency
 *
 * @author Zachary Dawson
 * @author Trevor Decker
 */
public abstract class PeriodicNode extends BuggyDecoratorNode {

    private final int runPeriod;
    private TimerTask timerTask;
    private Timer timer;

    /**
     * Create a new {@link PeriodicNode} decorator
     *
     * @param base   {@link BuggyNode} to decorate
     * @param period of the periodically executed portion of the node
     *               Note the timer needs to be started by running resume
     */
    protected PeriodicNode(BuggyNode base, int period, String name) {
        super(base, name);
        runPeriod = period;
        timerTask = new UpdateTask();
        pause();
    }

    protected synchronized void pause() {
        if (timer != null) {
            timer.cancel();
        }

    }

    protected synchronized void resume() {
        timer = new Timer(true);
        timer.scheduleAtFixedRate(timerTask, 0, runPeriod);

    }

    /**
     * Method run periodically by the {@link PeriodicNode}
     */
    protected abstract void update();

    /**
     * Task used to call the update method
     */
    private class UpdateTask extends TimerTask {

        @Override
        public void run() {
            update();
        }
    }
}