利用java实现UDP（二）

[振哥哥]

本帖子接 《利用java实现UDP》这个帖子：
客户端：
UDPClientBean.java

package UDPClient;

import java.io.*;
import java.net.*;

class UDPClientBean{

	private DatagramSocket dSocket;   
	private int ServerPort;
	private int ClientPort;
	private InetAddress ServerIP;
	private InetAddress ClientIP;
	private String content;
	
	//无参构造函数
	public UDPClientBean() throws SocketException,UnknownHostException {
		
		ServerPort = 1001;
		ClientPort =1111;
		content = "";	
		ClientIP = InetAddress.getLocalHost();
		ServerIP = InetAddress.getLocalHost();
		dSocket = new DatagramSocket(ClientPort);
	}
	//  信息发送函数
	public void sendToServer() throws IOException{
		byte[] Buffer = getContent().getBytes();   //将要发送的信息给Buffer变量
		DatagramPacket  dPacket  =  new DatagramPacket(Buffer,Buffer.length,getServerIP(),getServerPort());
		        //  创建DatagramPacket对象dPacket，并指定要发送对象的服务器的IP地址与端口号
		dSocket.send(dPacket);   // dSocket对象调用send函数发送信息
		setContent("");
	}
	//  信息接收函数
	public String receiveFromServer() throws IOException{
		byte[] buffer = new byte[1024];
		DatagramPacket dPacket = new DatagramPacket(buffer,buffer.length);   
 // 创建DatagramPacket对象dPacket
		dSocket.receive(dPacket);  // dSocket对象调用receive函数接收信息
		String receive_str = new String(dPacket.getData(),0,dPacket.getLength());
		return receive_str;    // 返回接收到的信息
	}
	// 下面都是UDPClientBean类的各个成员变量的get和set方法
	public DatagramSocket getdSocket() {
		return dSocket;
	}

	public void setdSocket(DatagramSocket dSocket) {
		this.dSocket = dSocket;
	}

	public int getServerPort() {
		return ServerPort;
	}

	public void setServerPort(int serverPort) {
		ServerPort = serverPort;
	}

	public String getContent() {
		return content;
	}

	public void setContent(String content) {
		this.content = content;
	}

	public InetAddress getServerIP() {
		return ServerIP;
	}

	public void setServerIP(InetAddress serverIP) {
		ServerIP = serverIP;
	}

	public int getClientPort() {
		return ClientPort;
	}

	public void setClientPort(int clientPort) {
		ClientPort = clientPort;
	}

	public InetAddress getClientIP() {
		return ClientIP;
	}
	public void setClientIP(InetAddress clientIP) {
		ClientIP = clientIP;
	}
}

UDPClient.java

package UDPClient;

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;
import javax.swing.*;

public class UDPClient extends JApplet {

	private String content;
	private UDPClientBean client;
	
	private JTextField jtf_ServerIP = new JTextField(10);
	private JTextField jtf_ServerPort = new JTextField(10);
	private JTextField jtf_ClientPort = new JTextField(10);
	
	private JButton jbt_Set= new JButton("设置");
	
	private JTextArea jta_ClientShow = new JTextArea();
	private JTextArea jta_ClientInput = new JTextArea();
	
	private JButton jbt_Send= new JButton("发送");
	private JButton jbt_Exit= new JButton("退出");

	public UDPClient(){
		JPanel jplClient11 = new JPanel();
		jplClient11.setLayout(new GridLayout(3,2));
		jplClient11.add(new JLabel("客户端端口:"));
		jplClient11.add(jtf_ClientPort);
		jplClient11.add(new JLabel("服务器地址:"));
		jplClient11.add(jtf_ServerIP);
		jplClient11.add(new JLabel("服务器端口:"));
		jplClient11.add(jtf_ServerPort);

		JPanel jplClient10= new JPanel();
		jplClient10.add(jplClient11);
		jplClient10.add(jbt_Set);
		JPanel jplClient21 = new JPanel();
		jplClient21.add(jbt_Send);
		jplClient21.add(jbt_Exit);
		JPanel jplClient31 = new JPanel();
		jplClient31.setLayout(new GridLayout(2,1));
		jplClient31.add(new JScrollPane(jta_ClientShow));
		jplClient31.add(new JScrollPane(jta_ClientInput));
		
		add(jplClient10,BorderLayout.NORTH);
		add(jplClient31,BorderLayout.CENTER);
		add(jplClient21,BorderLayout.SOUTH);	

		// 设置按钮触发事件
		jbt_Set.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e) {		
					try {
						client = new UDPClientBean(); //创建UDPClientBean对象
						int cliPort =  Integer.parseInt(jtf_ClientPort.getText());  
 //将客户机端口从jtf_ServerPort文本域中取出
						client.setClientPort(cliPort);   //将取出的cliPort给client对象的ClientPort成员变量
						String serIP = jtf_ServerIP.getText();   // 将服务器IP从jtf_ServerIP文本域中取出
						int serPort = Integer.parseInt(jtf_ServerPort.getText());    //将服务器端口从jtf_ServerPort文本域中取出
						client.setdSocket(new DatagramSocket(client.getClientPort(),client.getClientIP()));     // client对象调用setdSocket()函数，创建新Socket对象(此时客户机端口号为设定的端口号)		
						client.setServerIP(InetAddress.getByName(serIP));     
//将取出的serIP给client对象的ServerIP成员变量
						client.setServerPort(serPort);   //将取出的serPort给client对象的ServerPort成员变量
						jta_ClientShow.setText("将信息发送到IP为 "+jtf_ServerIP.getText()+"  端口为 "+jtf_ServerPort.getText()+"  的服务器上。\n");         // 将信息发送的对象的服务器的信息显示在jta_ClientShow区域中
					} catch (SocketException e2) {
						e2.printStackTrace();
					}  catch (UnknownHostException e1) {
						e1.printStackTrace();
					}catch (Exception e1) {
						e1.printStackTrace();
					}
			}
		});
		// 发送按钮触发事件
		jbt_Send.addActionListener(new ActionListener(){
			public void actionPerformed(ActionEvent e) {
				client.setContent("");
				content = jta_ClientInput.getText();    //取jta_ClientInput文本区域中要发送的信息
				client.setContent(content);     //将取出的信息给client对对象的content成员变量
				jta_ClientShow.setText(jta_ClientShow.getText()+"客户机发送："+content+"\n");    //  将要发送的信息显示在jta_ClientShow区域框中
				jta_ClientInput.setText(null);    //将jta_ClientInput文本区域置空
				String receive_str = null;
				try {
					client.sendToServer();	//  client对象调用信息发送函数
					
				} catch (IOException e1) {
					jta_ClientShow.setText(jta_ClientShow.getText()+"数据发送失败\n");
					e1.printStackTrace();
				}
				try {
					receive_str = client.receiveFromServer();    // client对象调用信息接收函数，并将结果返回给receive_str变量	
			   jta_ClientShow.setText(jta_ClientShow.getText()+receive_str+"\n"); 
                     // 将收到的信息显示在jta_ClientShow区域框中
				} catch (IOException e1) {
					jta_ClientShow.setText(jta_ClientShow.getText()+"数据接收失败\n");
					e1.printStackTrace();
				}  
			}
		});

		// 退出按钮触发事件
		jbt_Exit.addActionListener(new ActionListener() {
			public void actionPerformed(ActionEvent e) {
				client.getdSocket().close();
				System.exit(0);
			}
		});
	}
}

截图：



现在就是出现点“发送”按钮没有反应的情况，代码貌似很长，其实思想很简单，求大神们耐心看完……

[业余草]

1.确定是否触发了发送按钮，如果没有触发，则事件有问题。 2.触发了事件，检查是否发送了消息，如果没有发送消息，则可能是发送消息不正确导致的。 3.如果发送了消息，那可能就是接受端有问题，那就检查检查接收数据是否有不正确的地方导致的。 可能通过抓包，看看是否发送了。当然也有可能是乱码导致的。