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Returns the current time in milliseconds. Note that while the unit of time of
the return value is a millisecond, the granularity of the value depends on the
underlying operating system and may be larger. For example, many operating
systems measure time in units of tens of milliseconds.
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public class ClockAccuracyTest {
    public static void main(String args[]) {
        SimpleDateFormat formatter = new SimpleDateFormat("dd-MMM-yyyy HH:mm:ss:SSS");
        int size = 4000000;
        // create an array to hold millisecond times
        // and loop to capture them
        long times[] = new long[size];
        for (int i = 0; i < size; i++) {
            times[i] = System.currentTimeMillis();
        }
        // now display the unique times
        long time = times[0];
        long previousTime = times[0];
        long count = 0;
        Set<Long> deltas = new HashSet<Long>();       
        long delta = 0;
        long minDelta = Long.MAX_VALUE;
        long maxDelta = Long.MIN_VALUE;
    &