code: public static boolean isZero(byte[] bytes, int startPos, int length) {
          return !hasUnsafe() || !unalignedAccess() ?
                  isZeroSafe(bytes, startPos, length) :
                  PlatformDependent0.isZero(bytes, startPos, length);
      }
docs: Determine if a subsection of an array is zero.
  @param bytes The byte array.
  @param startPos The starting index (inclusive) in {@code bytes}.
  @param length The amount of bytes to check for zero.
  @return {@code false} if {@code bytes[startPos:startsPos+length)} contains a value other than zero.