【发布时间】：2020-11-11 21:06:56
【问题描述】：
我编写代码试图实现客户端服务器聊天。 我创建了两个 JFrame（客户端和服务器） 他们可以发送和接收消息，直到其中一个写“退出”，但在这种情况下存在问题。
客户端：
public class Client extends JFrame{
private JPanel contentPane;
private JTextField testo;
static JTextArea area;
static Socket client;
static DataInputStream dis;
static DataOutputStream dos;
public static void main(String[] args) throws UnknownHostException, IOException {
client=new Socket("127.0.0.1",1234);
dis=new DataInputStream(client.getInputStream());
dos=new DataOutputStream(client.getOutputStream());
try {
Client frame = new Client();
frame.setVisible(true);
String msg="";
while(msg!="exit") {
msg=dis.readUTF();
System.out.println(msg);
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Create the frame.
*/
public Client(){
System.out.println("Metodo Client-ingresso");
setTitle("Client");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 599, 401);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
testo = new JTextField();
testo.setBounds(10, 315, 421, 19);
contentPane.add(testo);
testo.setColumns(10);
area = new JTextArea();
area.setEditable(false);
area.setBounds(10, 10, 565, 295);
contentPane.add(area);
JButton bottone = new JButton("Invia");
bottone.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
area.append(testo.getText());
try {
String invia=testo.getText();
dos.writeUTF(invia);
if(invia=="Exit") {
client.close();
System.exit(0);
}
} catch (IOException e1) {
System.out.println("Client errore in Invio sul DOS");
}
}
});
bottone.setBounds(441, 315, 134, 21);
contentPane.add(bottone);
System.out.println("Uscita dal metodo client");
}
}
服务器端：
public class Server extends JFrame{
private JPanel contentPane;
private JTextField testo;
static JTextArea area;
static ServerSocket ss;
static Socket server;
static DataInputStream dis;
static DataOutputStream dos;
/**
* Launch the application.
* @throws IOException
*/
public static void main(String[] args) throws IOException {
ss=new ServerSocket(1234);
server=ss.accept();
dis=new DataInputStream(server.getInputStream());
dos=new DataOutputStream(server.getOutputStream());
try {
Server frame = new Server();
frame.setVisible(true);
String msg="";
while(msg!="exit") {
System.out.println("Il Server è qui");
msg=dis.readUTF();
System.out.println(msg);
}
} catch (Exception e) {
e.printStackTrace();
}
}
/**
* Create the frame.
*/
public Server() {
setTitle("Server");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setBounds(100, 100, 600, 419);
contentPane = new JPanel();
contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
setContentPane(contentPane);
contentPane.setLayout(null);
testo = new JTextField();
testo.setBounds(10, 329, 444, 19);
contentPane.add(testo);
testo.setColumns(10);
area = new JTextArea();
area.setEditable(false);
area.setBounds(10, 10, 566, 308);
contentPane.add(area);
JButton bottone = new JButton("Invia");
bottone.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
area.append(testo.getText());
try {
String invia=testo.getText();
dos.writeUTF(invia);
if(invia=="exit") {
ss.close();
server.close();
System.exit(0);
}
} catch (IOException e1) {
System.out.println("S errore in invio sul DOS.");
}
}
});
bottone.setBounds(464, 328, 112, 21);
contentPane.add(bottone);
}
}
问题出在这里：
while(msg!="exit") {
msg=dis.readUTF();
}
如果我写退出，while 循环永远不会结束，我需要使用蛮力关闭，所以由于 dis.readUTF 上的异常而出现错误。
谁能帮帮我？
【问题讨论】：
标签： user-interface server client windowbuilder