@Override
    public synchronized int read(byte[] buf, int off, int len) throws IOException {
      // fill the buffer with the next RPC message
      if (unwrappedRpcBuffer.remaining() == 0) {
        readNextRpcPacket();
      }
      // satisfy as much of the request as possible
      int readLen = Math.min(len, unwrappedRpcBuffer.remaining());
      unwrappedRpcBuffer.get(buf, off, readLen);
      return readLen;
    }
Get a SASL wrapped InputStream. Can be called only after saslConnect() has been called.
@return a SASL wrapped InputStream
hbase-client/src/main/java/org/apache/hadoop/hbase/security/HBaseSaslRpcClient.java