DataOutputStream out = null;
DataInputStream in = null;
try {
//connect to a datanode
IOStreamPair pair = connectToDN(socketFactory, connectToDnViaHostname,
encryptionKey, datanodes[j], timeout);
out = new DataOutputStream(new BufferedOutputStream(pair.out,
HdfsConstants.SMALL_BUFFER_SIZE));
in = new DataInputStream(pair.in);