Java TCP Client - Server

//***Client*******//

public static void main(String[] args) {
Socket socket;

InetAddress address;

DataOutputStream os;

try {
address = InetAddress.getByName("127.0.0.1");
socket = new Socket(address, 20000);
os = new DataOutputStream(socket.getOutputStream());
os.writeBytes("helllo");

os.close();
socket.close();

} catch (UnknownHostException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}

}
//***Server*******//
public static void main(String[] args) {
ServerSocket serverSocket;

InetAddress serverAddress;

DataInputStream is;

try {
serverAddress = InetAddress.getByName("127.0.0.1");

serverSocket = new ServerSocket(20000, 10, serverAddress);

Socket client = serverSocket.accept();

is = new DataInputStream(client.getInputStream());

String str = is.readLine();

System.out.print(str);

is.close();
client.close();
serverSocket.close();

} catch (IOException e) {

e.printStackTrace();
}

}