public static byte[] readByteArray(final DataInput in) throws IOException {
    int len = WritableUtils.readVInt(in);
    if (len < 0) {
      throw new NegativeArraySizeException(Integer.toString(len));
    }
    byte[] result = new byte[len];
    in.readFully(result, 0, len);
    return result;
  }
Read byte-array written with a WritableableUtils.vint prefix.
@param in Input to read from.
@return byte array read off <code>in</code>
@throws IOException e
hbase-common/src/main/java/org/apache/hadoop/hbase/util/Bytes.java