我编写了一个基本的isnatnt消息程序，但它只允许客户端连接到服务器。我会在代码中更改什么，以便接受多个客户端，而不是让他们排队等候。
Client.java
import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import java.awt.Color;
import java.awt.Font;
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;
private JTextField UsernameField;
private String Username;
Color RED = new Color(255,0,0);
Color ORANGE = new Color(255,128,0);
Color YELLOW = new Color(255,255,0);
Color LIGHT_GREEN = new Color(51,255,51);
Color GREEN = new Color(0,255,0);
Color DARK_GREEN = new Color(0,102,0);
Color LIGHT_BLUE = new Color(51,51,255);
Color BLUE = new Color(0,0,255);
Color DARK_BLUE = new Color(0,0,102);
Color PURPLE = new Color(153,0,153);
//constructor
public Client(String host){
super("Azrin IM");
serverIP = host;
userText = new JTextField("Enter Message Here.");
userText.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (userText.getText().equals("Enter Message Here.")) // User has not entered text yet
userText.setText("");
}
});
userText.setEditable(true);
UsernameField = new JTextField("Enter Username Here.");
UsernameField.addMouseListener(new MouseAdapter() {
public void mouseClicked(MouseEvent e) {
if (UsernameField.getText().equals("Enter Username Here.")) // User has not entered text yet
UsernameField.setText("");
}
});
add(new JLabel ("Enter Username Here."));
UsernameField.setEditable(true);
userText.addActionListener(
new ActionListener(){
public void actionPerformed(ActionEvent event){
Username = UsernameField.getText();
sendMessage(event.getActionCommand());
userText.setText("");
UsernameField.setText("");
}
}
);
add(userText, BorderLayout.SOUTH);
add (UsernameField, BorderLayout.NORTH);
chatWindow = new JTextArea();
add(new JScrollPane(chatWindow), BorderLayout.CENTER);
setSize(400,300);
setVisible(true);
}
//connect to server
public void startRunning(){
try{
connectToServer();
setupStreams();
whileChatting();
}catch(EOFException eofException){
showMessage("\n Client terminated connection");
}catch(IOException ioException){
ioException.printStackTrace();
}finally{
Disconnect();
}
}
//connect to server
private void connectToServer() throws IOException{
showMessage("Attempting connection... \n");
connection = new Socket(InetAddress.getByName(serverIP), 6969);
showMessage("Connected to: " + connection.getInetAddress().getHostName() );
}
//set up streams to send and receive messages
private void setupStreams() throws IOException{
output = new ObjectOutputStream(connection.getOutputStream());
output.flush();
input = new ObjectInputStream(connection.getInputStream());
showMessage("\n Now connected to Server! \n");
}
//while chatting with server
private void whileChatting() throws IOException{
ableToType(true);
do{
try{
message = (String) input.readObject();
showMessage("\n" + message);
}catch(ClassNotFoundException classNotfoundException){
showMessage("\n I dont know that object type");
}
}while(!message.equals(Username + ": END"));
}
//close the streams and sockets
private void Disconnect(){
showMessage("\n Disconnected.");
ableToType(false);
try{
output.close();
input.close();
connection.close();
}catch(IOException ioException){
ioException.printStackTrace();
}
}
//send messages to server
private void sendMessage(String message){
try{
output.writeObject(Username + ": " + message);
output.flush();
showMessage("\n" + Username + ": " + message);
if (message.equals("RED")){
chatWindow.setForeground(RED);
}
if (message.equals("ORANGE")){
chatWindow.setForeground(ORANGE);
}
if (message.equals("YELLOW")){
chatWindow.setForeground(YELLOW);
}
// I am aware I need to space these if staments better :) .
if (message.equals("LIGHT_GREEN")){
chatWindow.setForeground(LIGHT_GREEN);
}
if (message.equals("GREEN")){
chatWindow.setForeground(GREEN);
}
if (message.equals("DARK_GREEN")){
chatWindow.setForeground(DARK_GREEN);
}
if (message.equals("LIGHT_BLUE")){
chatWindow.setForeground(LIGHT_BLUE);
}
if (message.equals("BLUE")){
chatWindow.setForeground(BLUE);
}
if (message.equals("DARK_BLUE")){
chatWindow.setForeground(DARK_BLUE);
}
if (message.equals("PURPLE")){
chatWindow.setForeground(PURPLE);
}
}catch(IOException ioException){
chatWindow.append("\n something messed up sending message hoss!");
}
}
//change/update chatWindow
private void showMessage(final String m){
SwingUtilities.invokeLater(
new Runnable(){
public void run(){
chatWindow.append(m);
}
}
);
}
//gives user permission to type crap into the text box
private void ableToType(final boolean tof){
SwingUtilities.invokeLater(
new Runnable(){
public void run(){
userText.setEditable(tof);
}
}
);
}
}
ClientTest.java
import javax.swing.JFrame;
public class ClientTest {
public static void main(String[] args) {
Client charlie;
charlie = new Client("69.125.13.88");
charlie.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
charlie.startRunning();
}
}
Server.java
import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class Server extends JFrame{
private JTextField userText;
private JTextArea chatWindow;
private ObjectOutputStream output;
private ObjectInputStream input;
private ServerSocket server;
private Socket connection;
//constructor
public Server(){
super("Azrin IM Server");
userText = new JTextField();
userText.setEditable(false);
userText.addActionListener(
new ActionListener(){
public void actionPerformed(ActionEvent event){
sendMessage(event.getActionCommand());
userText.setText("");
}
}
);
add(userText, BorderLayout.NORTH);
chatWindow = new JTextArea();
add(new JScrollPane(chatWindow));
setSize(500,200);
setVisible(true);
}
//set up and run the server
public void startRunning(){
try{
server = new ServerSocket(6969, 100);
while(true){
try{
waitForConnection();
setupStreams();
whileChatting();
}catch(EOFException eofException){
showMessage("\n Server ended the connection! ");
}finally{
closeCrap();
}
}
}catch(IOException ioException){
ioException.printStackTrace();
}
}
//wait for connection, then display connection information
private void waitForConnection() throws IOException{
showMessage(" Waiting for someone to connect... \n");
connection = server.accept();
showMessage(" Now connected to " + connection.getInetAddress().getHostName());
}
//get stream to send and receive data
private void setupStreams() throws IOException{
output = new ObjectOutputStream(connection.getOutputStream());
output.flush();
input = new ObjectInputStream(connection.getInputStream());
showMessage("\n Streams are now setup! \n");
}
//during the chat conversation
private void whileChatting() throws IOException{
String message = " You are now connected! ";
sendMessage(message);
ableToType(true);
do{
try{
message = (String) input.readObject();
showMessage("\n" + message);
}catch(ClassNotFoundException classNotFoundException){
showMessage("\n idk wtf that user sent!");
}
}while(!message.equals("CLIENT - END"));
}
//close streams and sockets after you are done chatting
private void closeCrap(){
showMessage("\n Closing connections... \n");
ableToType(false);
try{
output.close();
input.close();
connection.close();
}catch(IOException ioException){
ioException.printStackTrace();
}
}
//send a message to client
private void sendMessage(String message){
try{
output.writeObject("Josh A - " + message);
output.flush();
showMessage("\nSERVER - " + message);
}catch(IOException ioException){
chatWindow.append("\n ERROR: DUDE I CANT SEND THAT MESSAGE");
}
}
//updates chatWindow
private void showMessage(final String text){
SwingUtilities.invokeLater(
new Runnable(){
public void run(){
chatWindow.append(text);
}
}
);
}
//let the user type stuff into their box
private void ableToType(final boolean tof){
SwingUtilities.invokeLater(
new Runnable(){
public void run(){
userText.setEditable(tof);
}
}
);
}
}
ServerTest.java
import javax.swing.JFrame;
public class ServerTest {
public static void main(String[] args) {
Server sally = new Server();
sally.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
sally.startRunning();
}
}
答案 0 :(得分：4)
这是“普通”线程示例，可能是您可能会发现的更常见的示例。这样做的问题是你可能失去对线程的控制，并且有数百个渐变的线程都在运行，消耗系统资源......
这很简单，并且确实展示了您需要实现的基本概念......
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
public class TestSocketThread {
// Need away to stop the program...
private static boolean acceptMore = true;
public static void main(String[] args) {
new TestSocketThread();
}
public TestSocketThread() {
ServerSocket serverSocket = null;
try {
serverSocket = new ServerSocket(6969, 100);
while (acceptMore) {
Socket socket = serverSocket.accept();
new Thread(new SocketThread(socket)).start();
}
} catch (IOException exp) {
exp.printStackTrace();
} finally {
try {
serverSocket.close();
} catch (Exception e) {
}
}
}
public class SocketThread implements Runnable {
private Socket socket;
public SocketThread(Socket socket) {
this.socket = socket;
}
@Override
public void run() {
// Process socket...
}
}
}
执行程序服务更灵活，可以对普通线程提供更好的管理控制，包括（根据此示例）固定线程池。
import java.io.IOException;
import java.net.ServerSocket;
import java.net.Socket;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;
public class ExecutorSocketTest {
// Need away to stop the program...
private static boolean acceptMore = true;
public static void main(String[] args) {
new ExecutorSocketTest();
}
public ExecutorSocketTest() {
ServerSocket serverSocket = null;
ExecutorService executorService = Executors.newFixedThreadPool(100);
try {
serverSocket = new ServerSocket(6969, 100);
while (acceptMore) {
Socket socket = serverSocket.accept();
executorService.submit(new SocketCallable(socket));
}
} catch (IOException exp) {
exp.printStackTrace();
} finally {
try {
serverSocket.close();
} catch (Exception e) {
}
executorService.shutdownNow();
}
}
/**
*
* @author swhitehead
*/
public class SocketCallable implements Callable {
private Socket socket;
public SocketCallable(Socket socket) {
this.socket = socket;
}
@Override
public Object call() throws Exception {
// Process socket requests...
return null;
}
}
}
你的工作现在就消失，阅读所有关于Concurrency in Java
的内容