以下应用程序是由java开发的聊天程序,当我使用本地IP地址时,客户端完全连接到服务器。但是当我使用我的外部IP地址从两台不同的机器将客户端连接到服务器时,服务器只是等待连接而没有任何反应。所以我需要的是使用外部IP将客户端连接到服务器。
客户端:java
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){
sendMessage(event.getActionCommand());
userText.setText("");
}
}
);
add(userText, BorderLayout.NORTH);
chatWindow = new JTextArea();
add(new JScrollPane(chatWindow), BorderLayout.CENTER);
setSize(300,150);
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{
closeCrap();
}
}
//connect to server
private void connectToServer() throws IOException{
showMessage("Attempting connection... \n");
connection = new Socket(InetAddress.getByName(serverIP), 6789);
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 Dude your streams are now good to go! \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("SERVER - END"));
}
//close the streams and sockets
private void closeCrap(){
showMessage("\n closing crap down...");
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("CLIENT - " + message);
output.flush();
showMessage("\nCLIENT - " + message);
}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);
}
}
);
}
}
客户端:测试
import javax.swing.JFrame;
public class ClientTest {
public static void main(String[] args) {
Client charlie;
charlie = new Client("127.0.0.1");
charlie.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
charlie.startRunning();
}
}
服务器: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("Buckys Instant Messenger");
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(300,150);
setVisible(true);
}
//set up and run the server
public void startRunning(){
try{
server = new ServerSocket(6789, 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("SERVER - " + 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);
}
}
);
}
}
服务器:测试
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:1)
您需要配置防火墙并设置端口转发。
端口转发是重要的一步。基本上你需要告诉你的路由器将所有传入的请求发送到指定的端口,程序可以在那里处理它们。
防火墙是另一个可能的问题,有时您的网络或计算机会阻止未知请求。