!7

static String OS_ARCH = System.getProperty("os.arch");
static boolean JRE_IS_64BIT_HOTSPOT;
static boolean COMPRESSED_REFS_ENABLED;
static String MANAGEMENT_FACTORY_CLASS = "java.lang.management.ManagementFactory";
static String HOTSPOT_BEAN_CLASS = "com.sun.management.HotSpotDiagnosticMXBean";

p {
  boolean is64Bit = false;
  final String x = System.getProperty("sun.arch.data.model");
  if (x != null) {
      is64Bit = x.contains("64");
  } else {
      if (OS_ARCH != null && OS_ARCH.contains("64")) {
          is64Bit = true;
      } else {
          is64Bit = false;
      }
  }
  boolean compressedOops = false;
  boolean is64BitHotspot = false;

  if (is64Bit) {
      try {
          final Class<?> beanClazz = Class.forName(HOTSPOT_BEAN_CLASS);
          // we use reflection for this, because the management factory is
          // not part
          // of Java 8's compact profile:
          final Object hotSpotBean = Class.forName(MANAGEMENT_FACTORY_CLASS).getMethod("getPlatformMXBean", Class.class)
                  .invoke(null, beanClazz);
          if (hotSpotBean != null) {

              is64BitHotspot = true;
              final Method getVMOptionMethod = beanClazz.getMethod("getVMOption", String.class);
              try {
                  final Object vmOption = getVMOptionMethod.invoke(hotSpotBean, "UseCompressedOops");
                  compressedOops = Boolean.parseBoolean(vmOption.getClass().getMethod("getValue").invoke(vmOption).toString());
              } catch (ReflectiveOperationException | RuntimeException e) {
                  is64BitHotspot = false;
              }
          }
      } catch (ReflectiveOperationException | RuntimeException e) {
          is64BitHotspot = false;
      }
  }

  JRE_IS_64BIT_HOTSPOT = is64BitHotspot;
  COMPRESSED_REFS_ENABLED = compressedOops;
  
  print("Is 64bit Hotspot JVM: " + JRE_IS_64BIT_HOTSPOT);
  print("Compressed Oops enabled: " + COMPRESSED_REFS_ENABLED);
  print("isCompressedOopsOffOn64Bit: " + isCompressedOopsOffOn64Bit());
}

static bool isCompressedOopsOffOn64Bit() {
  ret JRE_IS_64BIT_HOTSPOT && !COMPRESSED_REFS_ENABLED;
}