public void setDescription(String description) {
        this.description = description;
    }

    /**
     * <p>
     * Set whether or not the <code>Trigger</code> should be persisted in the
     * <code>{@link org.quartz.spi.JobStore}</code> for re-use after program
     * restarts.
     * </p>
     */
    public void setVolatility(boolean volatility) {
        this.volatility = volatility;
    }

    /**
     * <p>
     * Associate the <code>{@link Calendar}</code> with the given name with
     * this Trigger.
     * </p>
     * 
     * @param calendarName
     *          use <code>null</code> to dis-associate a Calendar.
     */
    public void setCalendarName(String calendarName) {
        this.calendarName = calendarName;
    }

    /**
     * <p>
     * Get the name of the <code>{@link Calendar}</code> associated with this
     * Trigger.
     * </p>
     * 
     * @return <code>null</code> if there is no associated Calendar.
     */
    public String getCalendarName() {
        return calendarName;
    }

    /**
     * <p>
     * Get the <code>JobDataMap</code> that is associated with the 
     * <code>Trigger</code>.
     * </p>
     * 
     * <p>
     * Changes made to this map during job execution are not re-persisted, and
     * in fact typically result in an <code>IllegalStateException</code>.
     * </p>
     */
    public JobDataMap getJobDataMap() {
        if (jobDataMap == null) jobDataMap = new JobDataMap();
        return jobDataMap;
    }


    /**
     * <p>
     * Set the <code>JobDataMap</code> to be associated with the 
     * <code>Trigger</code>.
     * </p>
     */
    public void setJobDataMap(JobDataMap jobDataMap) {
        this.jobDataMap = jobDataMap;
    }
    
    /**
     * <p>
     * Whether or not the <code>Trigger</code> should be persisted in the
     * <code>{@link org.quartz.spi.JobStore}</code> for re-use after program
     * restarts.
     * </p>
     * 
     * <p>
     * If not explicitly set, the default value is <code>false</code>.
     * </p>
     * 
     * @return <code>true</code> if the <code>Trigger</code> should be
     *         garbage collected along with the <code>{@link Scheduler}</code>.
     */
    public boolean isVolatile() {
        return volatility;
    }

    /**
     * <p>
     * Add the specified name of a <code>{@link TriggerListener}</code> to
     * the end of the <code>Trigger</code>'s list of listeners.
     * </p>
     */
    public void addTriggerListener(String name) {
        triggerListeners.add(name);
    }

    /**
     * <p>
     * Remove the specified name of a <code>{@link TriggerListener}</code>
     * from the <code>Trigger</code>'s list of listeners.
     * </p>
     * 
     * @return true if the given name was found in the list, and removed
     */
    public boolean removeTriggerListener(String name) {
        return triggerListeners.remove(name);
    }

    /**
     * <p>
     * Returns an array of <code>String</code> s containing the names of all
     * <code>{@link TriggerListener}</code> assigned to the <code>Trigger</code>,
     * in the order in which they should be notified.
     * </p>
     */
    public String[] getTriggerListenerNames() {
        String[] outNames = new String[triggerListeners.size()];
        return (String[]) triggerListeners.toArray(outNames);
    }

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     * 
     * <p>
     * Called when the <code>{@link Scheduler}</code> has decided to 'fire'
     * the trigger (execute the associated <code>Job</code>), in order to
     * give the <code>Trigger</code> a chance to update itself for its next
     * triggering (if any).
     * </p>
     * 
     * @see #executionComplete(JobExecutionContext, JobExecutionException)
     */
    public abstract void triggered(Calendar calendar);

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     * 
     * <p>
     * Called by the scheduler at the time a <code>Trigger</code> is first
     * added to the scheduler, in order to have the <code>Trigger</code>
     * compute its first fire time, based on any associated calendar.
     * </p>
     * 
     * <p>
     * After this method has been called, <code>getNextFireTime()</code>
     * should return a valid answer.
     * </p>
     * 
     * @return the first time at which the <code>Trigger</code> will be fired
     *         by the scheduler, which is also the same value <code>getNextFireTime()</code>
     *         will return (until after the first firing of the <code>Trigger</code>).
     *         </p>
     */
    public abstract Date computeFirstFireTime(Calendar calendar);

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     * 
     * <p>
     * Called after the <code>{@link Scheduler}</code> has executed the
     * <code>{@link org.quartz.JobDetail}</code> associated with the <code>Trigger</code>
     * in order to get the final instruction code from the trigger.
     * </p>
     * 
     * @param context
     *          is the <code>JobExecutionContext</code> that was used by the
     *          <code>Job</code>'s<code>execute(xx)</code> method.
     * @param result
     *          is the <code>JobExecutionException</code> thrown by the
     *          <code>Job</code>, if any (may be null).
     * @return one of the Trigger.INSTRUCTION_XXX constants.
     * 
     * @see #INSTRUCTION_NOOP
     * @see #INSTRUCTION_RE_EXECUTE_JOB
     * @see #INSTRUCTION_DELETE_TRIGGER
     * @see #INSTRUCTION_SET_TRIGGER_COMPLETE
     * @see #triggered(Calendar)
     */
    public abstract int executionComplete(JobExecutionContext context,
            JobExecutionException result);

    /**
     * <p>
     * Used by the <code>{@link Scheduler}</code> to determine whether or not
     * it is possible for this <code>Trigger</code> to fire again.
     * </p>
     * 
     * <p>
     * If the returned value is <code>false</code> then the <code>Scheduler</code>
     * may remove the <code>Trigger</code> from the <code>{@link org.quartz.spi.JobStore}</code>.
     * </p>
     */
    public abstract boolean mayFireAgain();

    /**
     * <p>
     * Get the time at which the <code>Trigger</code> should occur.
     * </p>
     */
    public abstract Date getStartTime();

    public abstract void setStartTime(Date startTime); 
    
    public abstract void setEndTime(Date endTime); 
    
    /**
     * <p>
     * Get the time at which the <code>Trigger</code> should quit repeating -
     * even if an assigned 'repeatCount' isn't yet satisfied.
     * </p>
     * 
     * @see #getFinalFireTime()
     */
    public abstract Date getEndTime();

    /**
     * <p>
     * Returns the next time at which the <code>Trigger</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 abstract Date getNextFireTime();

    /**
     * <p>
     * Returns the previous time at which the <code>Trigger</code> will fire.
     * If the trigger has not yet fired, <code>null</code> will be returned.
     */
    public abstract Date getPreviousFireTime();

    /**
     * <p>
     * Returns the next time at which the <code>Trigger</code> will fire,
     * after the given time. If the trigger will not fire after the given time,
     * <code>null</code> will be returned.
     * </p>
     */
    public abstract Date getFireTimeAfter(Date afterTime);

    /**
     * <p>
     * Returns the last time at which the <code>Trigger</code> will fire, if
     * the Trigger will repeat indefinitely, null will be returned.
     * </p>
     * 
     * <p>
     * Note that the return time *may* be in the past.
     * </p>
     */
    public abstract Date getFinalFireTime();

    /**
     * <p>
     * Set the instruction the <code>Scheduler</code> should be given for
     * handling misfire situations for this <code>Trigger</code>- the
     * concrete <code>Trigger</code> type that you are using will have
     * defined a set of additional <code>MISFIRE_INSTRUCTION_XXX</code>
     * constants that may be passed to this method.
     * </p>
     * 
     * <p>
     * If not explicitly set, the default value is <code>MISFIRE_INSTRUCTION_SMART_POLICY</code>.
     * </p>
     * 
     * @see #MISFIRE_INSTRUCTION_SMART_POLICY
     * @see #updateAfterMisfire(Calendar)
     * @see SimpleTrigger
     * @see CronTrigger
     */
    public void setMisfireInstruction(int misfireInstruction) {
        if (!validateMisfireInstruction(misfireInstruction))
                throw new IllegalArgumentException(
                        "The misfire instruction code is invalid for this type of trigger.");
        this.misfireInstruction = misfireInstruction;
    }

    protected abstract boolean validateMisfireInstruction(int misfireInstruction);

    /**
     * <p>
     * Get the instruction the <code>Scheduler</code> should be given for
     * handling misfire situations for this <code>Trigger</code>- the
     * concrete <code>Trigger</code> type that you are using will have
     * defined a set of additional <code>MISFIRE_INSTRUCTION_XXX</code>
     * constants that may be passed to this method.
     * </p>
     * 
     * <p>
     * If not explicitly set, the default value is <code>MISFIRE_INSTRUCTION_SMART_POLICY</code>.
     * </p>
     * 
     * @see #MISFIRE_INSTRUCTION_SMART_POLICY
     * @see #updateAfterMisfire(Calendar)
     * @see SimpleTrigger
     * @see CronTrigger
     */
    public int getMisfireInstruction() {
        return misfireInstruction;
    }

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     * 
     * <p>
     * To be implemented by the concrete classes that extend this class.
     * </p>
     * 
     * <p>
     * The implementation should update the <code>Trigger</code>'s state
     * based on the MISFIRE_INSTRUCTION_XXX that was selected when the <code>Trigger</code>
     * was created.
     * </p>
     */
    public abstract void updateAfterMisfire(Calendar cal);

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     * 
     * <p>
     * To be implemented by the concrete class.
     * </p>
     * 
     * <p>
     * The implementation should update the <code>Trigger</code>'s state
     * based on the given new version of the associated <code>Calendar</code>
     * (the state should be updated so that it's next fire time is appropriate
     * given the Calendar's new settings). 
     * </p>
     * 
     * @param cal
     */
    public abstract void updateWithNewCalendar(Calendar cal, long misfireThreshold);

    /**
     * <p>
     * Validates whether the properties of the <code>JobDetail</code> are
     * valid for submission into a <code>Scheduler</code>.
     * 
     * @throws IllegalStateException
     *           if a required property (such as Name, Group, Class) is not
     *           set.
     */
    public void validate() throws SchedulerException {
        if (name == null)
                throw new SchedulerException("Trigger's name cannot be null",
                        SchedulerException.ERR_CLIENT_ERROR);

        if (group == null)
                throw new SchedulerException("Trigger's group cannot be null",
                        SchedulerException.ERR_CLIENT_ERROR);

        if (jobName == null)
                throw new SchedulerException(
                        "Trigger's related Job's name cannot be null",
                        SchedulerException.ERR_CLIENT_ERROR);

        if (jobGroup == null)
                throw new SchedulerException(
                        "Trigger's related Job's group cannot be null",
                        SchedulerException.ERR_CLIENT_ERROR);
    }

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     * 
     * <p>
     * Usable by <code>{@link org.quartz.spi.JobStore}</code>
     * implementations, in order to facilitate 'recognizing' instances of fired
     * <code>Trigger</code> s as their jobs complete execution.
     * </p>
     * 
     *  
     */
    public void setFireInstanceId(String id) {
        this.fireInstanceId = id;
    }

    /**
     * <p>
     * This method should not be used by the Quartz client.
     * </p>
     */
    public String getFireInstanceId() {
        return fireInstanceId;
    }

    /**
     * <p>
     * Return a simple string representation of this object.
     * </p>
     */
    public String toString() {
        return "Trigger '" + getFullName() + "':  triggerClass: '"
                + getClass().getName() + " isVolatile: " + isVolatile()
                + " calendar: '" + getCalendarName() + "' misfireInstruction: "
                + getMisfireInstruction() + " nextFireTime: " + getNextFireTime();
    }

    /**
     * <p>
     * Compare the next fire time of this <code>Trigger</code> to that of
     * another.
     * </p>
     */
    public int compareTo(Object obj) {
        Trigger other = (Trigger) obj;

        Date myTime = getNextFireTime();
        Date otherTime = other.getNextFireTime();

        if (myTime == null && otherTime == null) return 0;

        if (myTime == null) return 1;

        if (otherTime == null) return -1;

        if(myTime.before(otherTime))
            return -1;

        if(myTime.after(otherTime))
            return 1;
        
        return 0;
    }

    public boolean equals(Object obj) {
        if (!(obj instanceof Trigger)) return false;

        Trigger other = (Trigger) obj;

        if (!other.getName().equals(getName())) return false;
        if (!other.getGroup().equals(getGroup())) return false;

        return true;
    }
    
    
    public int hashCode() {
        return getFullName().hashCode(); 
    }
    
    public Object clone() {
        Trigger copy;
        try {
            copy = (Trigger) super.clone();
        } catch (CloneNotSupportedException ex) {
            throw new IncompatibleClassChangeError("Not Cloneable.");
        }
        return copy;
    }

}