TestRoots/watchdog

package nl.tudelft.watchdog.core.logic.ui;

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

import nl.tudelft.watchdog.core.logic.interval.IDEIntervalManagerBase;
import nl.tudelft.watchdog.core.logic.ui.events.WatchDogEventType;
import nl.tudelft.watchdog.core.util.WatchDogGlobals;
import nl.tudelft.watchdog.core.util.WatchDogLogger;

/**
 * Checks whether the time progress according to the system's time is in
 * accordance with its schedule. If not, closes all intervals for the last
 * recorded time and starts completely fresh intervals. Used to detect a system
 * suspend.
 */
public class TimeSynchronityChecker extends RegularCheckerBase {

    private static final int UPDATE_RATE = 1 * 60 * 1000;

    private final IDEIntervalManagerBase intervalManager;

    /** Constructor. */
    public TimeSynchronityChecker(IDEIntervalManagerBase intervalManager) {
        super(UPDATE_RATE);
        this.intervalManager = intervalManager;
        timer = new Timer(true);
        startTimeCheckerOnce();
    }

    /** Subclasses call this method from their constructor. */
    protected void startTimeCheckerOnce() {
        if (task != null) {
            task.cancel();
        }
        task = new TimeSynchronityTimerTask();
        timer.schedule(task, updateRate);
    }

    private class TimeSynchronityTimerTask extends TimerTask {

        long previousExecutionDate;

        private TimeSynchronityTimerTask() {
            previousExecutionDate = System.currentTimeMillis();
        }

        @Override
        public void run() {
            if (WatchDogGlobals.isActive) {
                // do not execute this task unless WatchDog has properly boot-up

                long executionDate = System.currentTimeMillis();
                long delta = executionDate - previousExecutionDate;
                boolean deltaIsWithinReasonableBoundaries = delta >= UPDATE_RATE
                        && delta <= UPDATE_RATE * 1.16;
                if (!deltaIsWithinReasonableBoundaries) {
                    WatchDogLogger.getInstance().logInfo(
                            "System suspend detected!");
                    intervalManager.closeAllIntervals(new Date(
                            previousExecutionDate + UPDATE_RATE));
                    intervalManager.generateAndSetSessionSeed();
                    WatchDogEventType.START_IDE.process(this);
                    WatchDogEventType.editorSpecificImplementation.processPerspectiveInterval();
                }
            }

            startTimeCheckerOnce();
            previousExecutionDate = System.currentTimeMillis();
        }
    }

}