Question

Java的udp客户、服务器通信，有界面，用ip地址连接，服务器能保存通信的信息到一个文件夹

…………………………

Answer 1

服务端和客户端代码：
public class Main {
public static void main(String[] args) throws Exception {

UDPServer server = new UDPServer();
server.start(6666, "logs/udpserver.txt");
Thread.sleep(500);
UDPClient client = new UDPClient();
client.start(6666);
for(int i = 0; i < 10; i++) {
client.send("Hello： " + i + "\n");
}
client.stop();
Thread.sleep(500);
server.stop();
}
}

class UDPServer implements Runnable{

private DatagramSocket ds;

private boolean running = false;

private Thread thread = null;

private FileOutputStream fos;

public void start(int port, String logFilename) throws Exception{
if(!running) {
running = true;
ds = new DatagramSocket(new InetSocketAddress("127.0.0.1", 6666));
fos = new FileOutputStream(logFilename);
thread = new Thread(this);
thread.start();
}
}

@Override
public void run() {
while(running) {
try {
byte[] buf = new byte[2048];
DatagramPacket dp = new DatagramPacket(buf, buf.length);
ds.setSoTimeout(500);
try {
ds.receive(dp);
fos.write(dp.getData(), 0, dp.getLength());
} catch (SocketTimeoutException e) {
}
} catch (IOException e) {
e.printStackTrace();
break;
}
}
try {
fos.close();
} catch (IOException e) {
e.printStackTrace();
}
ds.close();
}

public void stop() {
if(running) {
running = false;
thread.interrupt();
}
}
}

class UDPClient{

private DatagramSocket ds;

public void start(int port) throws Exception{
ds = new DatagramSocket(0);
ds.connect(new InetSocketAddress("127.0.0.1", 6666));
}

public void send(String message) {
byte[] data = message.getBytes();
DatagramPacket dp = new DatagramPacket(data, data.length);
try {
ds.send(dp);
} catch (IOException e) {
e.printStackTrace();
}
}

public void stop() {
if (ds != null) {
ds.close();
}
}
}
界面代码你自己写吧

追问

这位大哥，运行有错啊……能不能把界面一起能过来啊 加分啊

追答

什么错？
server.start(6666, "logs/udpserver.txt");
这个换成你想要输出的文件，默认是在当前是要有一个logs目录 的

追问

Description Resource Path Location Type
DatagramPacket cannot be resolved to a type Main.java WO/src line 43 Java Problem
这里错了 怎么弄？

追答

在最前面加：
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketTimeoutException;

追问

还是运行不出来 Exception in thread "main" java.io.FileNotFoundException: logs\udpserver.txt (系统找不到指定的路径。)
at java.io.FileOutputStream.open(Native Method)
at java.io.FileOutputStream.(Unknown Source)
at java.io.FileOutputStream.(Unknown Source)
at UDPServer.start(Main.java:38)
at Main.main(Main.java:11)

追答

这个要换成你本机上存在的文件
简单点你就 把"logs/udpserver.txt" 改成 udpserver.txt就OK了

追问

好了 但是啥都没出来啊 无语了 界面又没有 …………