/** The offset to the first element in a byte array. */
      static final int BYTE_ARRAY_BASE_OFFSET = theUnsafe.arrayBaseOffset(byte[].class);

      static {
        // fall back to the safer pure java implementation unless we're in
        // a 64-bit JVM with an 8-byte aligned field offset.
        if (!("64".equals(System.getProperty("sun.arch.data.model"))
            && (BYTE_ARRAY_BASE_OFFSET % 8) == 0