crontrigger.java

Quartz 是个开源的作业调度框架

     * </p>
     */
    public CronTrigger(String name, String group, String jobName,
            String jobGroup, String cronExpression, TimeZone timeZone)
            throws ParseException {
        this(name, group, jobName, jobGroup, null, null, cronExpression,
                timeZone);
    }

    /**
     * <p>
     * Create a <code>CronTrigger</code> that will occur at the given time,
     * until the given end time.
     * </p>
     * 
     * <p>
     * If null, the start-time will also be set to the current time, the time
     * zone will be set the the system's default.
     * </p>
     * 
     * @param startTime
     *          A <code>Date</code> set to the time for the <code>Trigger</code>
     *          to fire.
     * @param endTime
     *          A <code>Date</code> set to the time for the <code>Trigger</code>
     *          to quit repeat firing.
     */
    public CronTrigger(String name, String group, String jobName,
            String jobGroup, Date startTime, Date endTime, String cronExpression)
            throws ParseException {
        super(name, group, jobName, jobGroup);

        setCronExpression(cronExpression);

        if (startTime == null) startTime = new Date();
        setStartTime(startTime);
        if (endTime != null) setEndTime(endTime);
        setTimeZone(TimeZone.getDefault());

    }

    /**
     * <p>
     * Create a <code>CronTrigger</code> with fire time dictated by the
     * <code>cronExpression</code> resolved with respect to the specified
     * <code>timeZone</code> occuring from the <code>startTime</code> until
     * the given <code>endTime</code>.
     * </p>
     * 
     * <p>
     * If null, the start-time will also be set to the current time. If null,
     * the time zone will be set to the system's default.
     * </p>
     * 
     * @param name
     *          of the <code>Trigger</code>
     * @param group
     *          of the <code>Trigger</code>
     * @param jobName,
     *          name of the <code>{@link org.quartz.JobDetail}</code>
     *          executed on firetime
     * @param jobGroup,
     *          group of the <code>{@link org.quartz.JobDetail}</code>
     *          executed on firetime
     * @param startTime
     *          A <code>Date</code> set to the earliest time for the <code>Trigger</code>
     *          to start firing.
     * @param endTime
     *          A <code>Date</code> set to the time for the <code>Trigger</code>
     *          to quit repeat firing.
     * @param cronExpression,
     *          A cron expression dictating the firing sequence of the <code>Trigger</code>
     * @param timeZone,
     *          Specifies for which time zone the <code>cronExpression</code>
     *          should be interprted, i.e. the expression 0 0 10 * * ?, is
     *          resolved to 10:00 am in this time zone.
     * @throws ParseException
     *           if the <code>cronExpression</code> is invalid.
     */
    public CronTrigger(String name, String group, String jobName,
            String jobGroup, Date startTime, Date endTime,
            String cronExpression, TimeZone timeZone) throws ParseException {
        super(name, group, jobName, jobGroup);

        setCronExpression(cronExpression);

        if (startTime == null) startTime = new Date();
        setStartTime(startTime);
        if (endTime != null) setEndTime(endTime);
        if (timeZone == null) {
            setTimeZone(TimeZone.getDefault());
        } else {
            setTimeZone(timeZone);
        }
    }

    /*
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     * 
     * Interface.
     * 
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     */
    
    public Object clone() {
    	CronTrigger copy = (CronTrigger) super.clone();
        copy.setCronExpression((CronExpression)cronEx.clone());
        return copy;
    }

    public void setCronExpression(String cronExpression) throws ParseException {
        this.cronEx = new CronExpression(cronExpression);
        this.cronEx.setTimeZone(getTimeZone());
    }

    public String getCronExpression() {
        return cronEx == null ? null : cronEx.getCronExpression();
    }

    public void setCronExpression(CronExpression cronExpression) {
    	this.cronEx = cronExpression;
    	this.timeZone = cronExpression.getTimeZone();
    }
    
    /**
     * <p>
     * Get the time at which the <code>CronTrigger</code> should occur.
     * </p>
     */
    public Date getStartTime() {
        return this.startTime;
    }

    public void setStartTime(Date startTime) {
        if (startTime == null)
                throw new IllegalArgumentException("Start time cannot be null");

        Date eTime = getEndTime();
        if (eTime != null && startTime != null && eTime.before(startTime))
            throw new IllegalArgumentException(
            "End time cannot be before start time");
        
        // round off millisecond...
        // Note timeZone is not needed here as parameter for
        // Calendar.getInstance(),
        // since time zone is implicit when using a Date in the setTime method.
        Calendar cl = Calendar.getInstance();
        cl.setTime(startTime);
        cl.set(Calendar.MILLISECOND, 0);

        this.startTime = cl.getTime();
    }

    /**
     * <p>
     * Get the time at which the <code>CronTrigger</code> should quit
     * repeating - even if repeastCount isn't yet satisfied.
     * </p>
     * 
     * @see #getFinalFireTime()
     */
    public Date getEndTime() {
        return this.endTime;
    }

    public void setEndTime(Date endTime) {
        Date sTime = getStartTime();
        if (sTime != null && endTime != null && sTime.after(endTime))
                throw new IllegalArgumentException(
                        "End time cannot be before start time");

        this.endTime = endTime;
    }

    /**
     * <p>
     * Returns the next time at which the <code>CronTrigger</code> will fire.
     * If the trigger will not fire again, <code>null</code> will be
     * returned. The value returned is not guaranteed to be valid until after
     * the <code>Trigger</code> has been added to the scheduler.
     * </p>
     */
    public Date getNextFireTime() {
        return this.nextFireTime;
    }

    /**
     * <p>
     * Returns the previous time at which the <code>CronTrigger</code> will
     * fire. If the trigger has not yet fired, <code>null</code> will be
     * returned.
     */
    public Date getPreviousFireTime() {
        return this.previousFireTime;
    }

    /**
     * <p>
     * Sets the next time at which the <code>CronTrigger</code> will fire.
     * <b>This method should not be invoked by client code.</b>
     * </p>
     */
    public void setNextFireTime(Date nextFireTime) {
        this.nextFireTime = nextFireTime;
    }

    /**
     * <p>
     * Set the previous time at which the <code>SimpleTrigger</code> fired.
     * </p>
     * 
     * <p>
     * <b>This method should not be invoked by client code.</b>
     * </p>
     */
    public void setPreviousFireTime(Date previousFireTime) {
        this.previousFireTime = previousFireTime;
    }

    /**
     * <p>
     * Returns the time zone for which the <code>cronExpression</code> of
     * this <code>CronTrigger</code> will be resolved.
     * </p>
     */
    public TimeZone getTimeZone() {
    	
    	if(cronEx != null) return cronEx.getTimeZone();
    	
        if (timeZone == null) timeZone = TimeZone.getDefault();
        return timeZone;
    }

    /**
     * <p>
     * Sets the time zone for which the <code>cronExpression</code> of this
     * <code>CronTrigger</code> will be resolved.
     * </p>
     */
    public void setTimeZone(TimeZone timeZone) {
    	if(cronEx != null) cronEx.setTimeZone(timeZone);
    	this.timeZone = timeZone;
    }

    /**
     * <p>
     * Returns the next time at which the <code>CronTrigger</code> will fire,
     * after the given time. If the trigger will not fire after the given time,
     * <code>null</code> will be returned.
     * </p>
     * 
     * <p>
     * Note that the date returned is NOT validated against the related
     * org.quartz.Calendar (if any)
     * </p>
     */
    public Date getFireTimeAfter(Date afterTime) {
        if (afterTime == null) afterTime = new Date();

        if (startTime.after(afterTime))
                afterTime = new Date(startTime.getTime() - 1000l);

        Date pot = getTimeAfter(afterTime);
        if (endTime != null && pot != null && pot.after(endTime)) return null;

        return pot;
    }

    /**
     * <p>
     * Returns the final time at which the <code>CronTrigger</code> will
     * fire.
     * </p>
     * 
     * <p>
     * Note that the return time *may* be in the past. and the date returned is
     * not validated against org.quartz.calendar
     * </p>
     */
    public Date getFinalFireTime() {
        if (this.endTime != null) return getTimeBefore(this.endTime);
        else
            return null;
    }

    /**
     * <p>
     * Determines whether or not the <code>CronTrigger</code> will occur
     * again.
     * </p>
     */
    public boolean mayFireAgain() {
        return (getNextFireTime() != null);
    }

    protected boolean validateMisfireInstruction(int misfireInstruction) {
        if (misfireInstruction < MISFIRE_INSTRUCTION_SMART_POLICY)
                return false;

        if (misfireInstruction > MISFIRE_INSTRUCTION_DO_NOTHING) return false;

        return true;
    }

    /**
     * <p>
     * Updates the <code>CronTrigger</code>'s state based on the
     * MISFIRE_INSTRUCTION_XXX that was selected when the <code>SimpleTrigger</code>
     * was created.
     * </p>
     * 
     * <p>
     * If the misfire instruction is set to MISFIRE_INSTRUCTION_SMART_POLICY,
     * then the following scheme will be used: <br>
     * <ul>
     * <li>The instruction will be interpreted as <code>MISFIRE_INSTRUCTION_FIRE_ONCE_NOW</code>
     * </ul>
     * </p>
     */
    public void updateAfterMisfire(org.quartz.Calendar cal) {
        int instr = getMisfireInstruction();

        if (instr == MISFIRE_INSTRUCTION_SMART_POLICY)
                instr = MISFIRE_INSTRUCTION_FIRE_ONCE_NOW;