PeriodicSample comparisons

If stamp marks end of period, should it be minus operator here, not plus?
But I may be wrong.

iris/src/us/mn/state/dot/tms/server/PeriodicSample.java

Lines 46 to 50 in 93ef16f

    
           public int compareTo(PeriodicSample other) { 
        
           	long ms = stamp + periodMillis(); 
        
           	long oms = other.stamp + other.periodMillis(); 
        
           	return (int) (ms - oms); 
        
           }

And by the way, you can use Long.compare() method.

The purpose of this compareTo is for ordering in PeriodicSampleCache:

iris/src/us/mn/state/dot/tms/server/PeriodicSampleCache.java

Lines 133 to 136 in 93ef16f

    
           	/** Collection of periodic samples.  Every sample is guaranteed to 
        
           	 * have the same sampling period. */ 
        
           	private final ConcurrentSkipListSet<PeriodicSample> samples = 
        
           		new ConcurrentSkipListSet<PeriodicSample>();

Here, periodMillis is guaranteed to be the same between all samples. In short, I don't think adding or subtracting makes any difference. If I was writing this code now, I would use a dedicated Comparator instead of natural ordering.

	public int compareTo(PeriodicSample other) {
	long ms = stamp + periodMillis();
	long oms = other.stamp + other.periodMillis();
	return (int) (ms - oms);
	}

	/** Collection of periodic samples. Every sample is guaranteed to
	* have the same sampling period. */
	private final ConcurrentSkipListSet<PeriodicSample> samples =
	new ConcurrentSkipListSet<PeriodicSample>();