Question

Below my code Gives me strange Results, Obviously you must be getting 1000, but in reality do not expect anything below 3500. I got 3500-4500 on different runs. And I read some where that Thread.sleep is completely unreliable. Why does java not Depcrecate it, if its useless?

Is There Any solution For that?

class MyClass {

            public static void main ( String[] args ) {

                    long start, end, took;

                    start = System.currentTimeMillis();
                    for ( int i=0; i<200; i++) {
                            try {
                            Thread.sleep (5);
                            } catch ( Exception ex ) {
                                    ex.printStackTrace();
                            }
                    }
                    end = System.currentTimeMillis();
                    System.out.println("Start :: " + start);
                    System.out.println("end :: " + end);
                    took = end -start;
                    System.out.println ("Took: " + took);

            }

Answer 1

Precise timing in Thread.sleep is not guaranteed and that’s precisely the reason you’re getting different timings on different runs.

Better to use RealTimeThread for real time calculation in Java.