private static void unsafeCopy(Object src, long srcAddr, Object dst, long destAddr, long len) {
    while (len > 0) {
      long size = (len > UNSAFE_COPY_THRESHOLD) ? UNSAFE_COPY_THRESHOLD : len;
      HBasePlatformDependent.copyMemory(src, srcAddr, dst, destAddr, size);
      len -= size;
      srcAddr += size;
      destAddr += size;
    }
  }
Copies the bytes from given array's offset to length part into the given buffer.
@param src        source array
@param srcOffset  offset into source buffer
@param dest       destination buffer
@param destOffset offset into destination buffer
@param length     length of data to copy
hbase-common/src/main/java/org/apache/hadoop/hbase/util/UnsafeAccess.java