Intermediate Java(57) - showMessage and ableToType

import java.io.*;

import java.net.*;

import java.awt.*;

import java.awt.event.*;

import javax.swing.*;

public class Client extends JFrame{

private JTextField userText;

private JTextArea chatwindow;

private ObjectOutputStream output;

private ObjectInputStream input;

private String message = "";

private String serverIP;

private Socket connection;

//constructor

public Client(String host){

super("Client mofo!");

serverIP = host;

userText = new JTextField();

userText.setEditable(false);

userText.addActionListener(

new ActionListener(){

public void actionPerformed(ActionEvent event){

sendData(event.getActionCommand());

userText.setText("");

}

}

);

add(userText, BorderLayout.NORTH);

chatwindow = new JTextArea();

add(new JScrollPane(chatwindow), BorderLayout.CENTER);

setSize(400,200);

setVisible(true);

}

//連接到服務器(Server)

public void startRunning(){

try{

connectToServer();

setupStreams();

whileChatting();

}catch(EOFException eofException){

showMessage("\n Client terminated connection");

}catch(IOException ioException){

ioException.printStackTrace();

}finally{

closeCrap();

}

}

//connectToServer函數

private void connectToServer() throws IOException{

showMessage("Attempting connection...\n");

connection = new Socket(InetAddress.getByName(serverIP),6789);

showMessage("Connected to:" + connection.getInetAddress().getHostName());

}

//設置發送和接收消息的Stream

private void setupStreams() throws IOException{

output =new ObjectOutputStream(connection.getOutputStream());

output.flush();

input = new ObjectInputStream(connection.getInputStream());

showMessage("\nyour streams are now good to go");

}

//當與服務器聊天

private void whilechatting() throws IOException{

ableToType(true);

do{

try{

message = (String) input.readObject();

showMessage("\n" + message);

}catch(ClassNotFoundException classNotfoundException){

showMessage("\n I don't know that object type");

}

}while(!message.equals("SERVER - END"));

}

//關閉Streams和connection

private void closeCrap(){

showMessage("\n closing crap down...");

ableToType(false);

try{

output.close();

input.close();

connection.close();

}catch(IOException ioException){

ioException.printStackTrace();

}

}

//發送消息到服務器

private void sendData(String message){

try{

output.writeObject("CLIENT - " + message);

output.flush();

showMessage("\nCLIENT - " +message);

}catch(IOException ioException){

chatwindow.append("\n Can not send the message!");

}

}

//更新chatwindow

private void showMessage(final String m){

SwingUtilities.invokeLater(

new Runnable(){

public void run(){

chatwindow.append(m);

}

}

);

}

//給用戶的權限，在文本框中鍵入

private void ableToType(final boolean tof){

SwingUtilities.invokeLater(

new Runnable(){

public void run(){

userText.setEditable(tof);

}

}

);

}

}

在這個class中的所有的意義，比如Server一樣