Geek asks and answers

How bad is the new Thread (). Sleep versus Thread.sleep in terms of CPU and memory usage?

I know that sleep should be available in a static context. However, I need more resources so that I can protect this management. Most of the legacy codes that I'm processing now use the new Thread (). Sleep instead of Thread.sleep.

How bad is that?

for (int c = 0; c < 5; c++) {
    new Thread().sleep(5000);
}

compared to this?

for (int c = 0; c < 5; c++) {
    Thread.sleep(5000);
}

EDIT:

    final long start = System.currentTimeMillis();
    System.out.println("Total memory: " + Runtime.getRuntime().totalMemory());
    System.out.println("Free memory: " + Runtime.getRuntime().freeMemory());
    System.out.println("===========================");
    for (int c = 0; c < 5; c++) {
        new Thread().sleep(5000);
        System.out.println("Used memory: " + (Runtime.getRuntime().totalMemory() - Runtime.getRuntime().freeMemory()));
        System.out.println("===========================");
    }
    System.out.println("Total memory: " + Runtime.getRuntime().totalMemory());
    System.out.println("Free memory: " + Runtime.getRuntime().freeMemory());
    System.out.println("===========================");
    System.out.println("Time elapsed: " + (System.currentTimeMillis() - start) + " milliseconds");

Result (new thread (). Sleep):

Total memory: 5177344
Free memory: 4990904
===========================
Used memory: 186440
===========================
Used memory: 205136
===========================
Used memory: 205136
===========================
Used memory: 205136
===========================
Used memory: 205136
===========================
Total memory: 5177344
Free memory: 4972208
===========================
Time elapsed: 24938 milliseconds

Result (Thread.sleep):

Total memory: 5177344
Free memory: 4990904
===========================
Used memory: 186440
===========================
Used memory: 186440
===========================
Used memory: 204848
===========================
Used memory: 204848
===========================
Used memory: 204848
===========================
Total memory: 5177344
Free memory: 4972496
===========================
Time elapsed: 24938 milliseconds
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