double_fun.java

   public static void main(String[] args) {
      final ExecutorService executorService = Executors.newFixedThreadPool(2);
      final int tests = 5;
      final int iterations = 10_000_000;
      final int length = 64;
      final AtomicBoolean releaser = new AtomicBoolean();
      final double[] values = new double[length];
      final AtomicBoolean finished = new AtomicBoolean(false);
      Arrays.fill(values, Double.MAX_VALUE);
      executorService.submit(() -> {
         for (int t = 0; t < tests; t++) {
            for (int i = 0; i < iterations; i++) {
               final boolean reverse = i % 2 == 0;
               for (int v = 0; v < length; v++) {
                  values[v] = reverse ? Double.MIN_VALUE : Double.MAX_VALUE;
               }
               releaser.lazySet(true);
            }
         }
         finished.lazySet(true);

      });
      executorService.submit(() -> {
         while (!finished.get()) {
            if (releaser.get()) {
               for (int v = 0; v < length; v++) {
                  final double value = values[v];
                  if (value != Double.MAX_VALUE && value != Double.MIN_VALUE) {
                     System.err.println("Non atomic write of a double: " + Long.toBinaryString(Double.doubleToRawLongBits(value)));
                  }
               }
            }
         }
      });
      executorService.shutdown();
   }