java - BindException：地址已在使用中

问题描述

我正在尝试使用 Java 进行套接字编程。为了让事情顺利进行，我尝试了一个非常简单的服务器和客户端代码片段，如下所示

public class Server {

    //initialize socket and input stream
    private Socket socket = null;
    private ServerSocket server = null;
    private DataInputStream in = null;

    public Server(int port) {
        // starts server and waits for a connection
        while (true) {
            try{
                server = new ServerSocket(port);
                System.out.println("Server started");
                System.out.println("Waiting for a client ...");
                socket = server.accept();
                System.out.println("Client accepted");
                // takes input from the client socket
                in = new DataInputStream(
                        new BufferedInputStream(socket.getInputStream()));
                String line = "";
                // reads message from client until "Over" is sent
                while (!line.equals("Over"))
                {
                    try
                    {
                        line = in.readUTF();
                        System.out.println(line);
                    }
                    catch(IOException i)
                    {
                        System.out.println(i);
                    }
                }
                System.out.println("Closing connection");
                // close connection
                socket.shutdownInput();
                socket.shutdownOutput();
                socket.close();
                in.close();
            }
            catch(IOException i){
                System.out.println(i);
            }
        }
    }

    public static void main(String args[]) {
        new Server(5000);
    }
}

Client.java 如下所示

public class Client {

    // initialize socket and input output streams
    private Socket socket = null;
    private DataInputStream input = null;
    private DataOutputStream out = null;
    // constructor to put ip address and port
    public Client(String address, int port)
    {
        // establish a connection
        try
        {
            socket = new Socket(address, port);
            System.out.println("Connected");
            // takes input from terminal
            input = new DataInputStream(System.in);
            // sends output to the socket
            out = new DataOutputStream(socket.getOutputStream());
        }
        catch(UnknownHostException u)
        {
            System.out.println(u);
        }
        catch(IOException i)
        {
            System.out.println(i);
        }// string to read message from input
        String line = "";
        // keep reading until "Over" is input
        while (!line.equals("Over"))
        {
            try
            {
                line = input.readLine();
                out.writeUTF(line);
            }
            catch(IOException i)
            {
                System.out.println(i);
            }
        }
        // close the connection
        try
        {
            input.close();
            out.close();
            socket.close();
        }
        catch(IOException i)
        {
            System.out.println(i);
        }
    }
    public static void main(String args[]) {
        Client client = new Client("127.0.0.1", 5000);
    }
}

它适用于与客户端的第一次连接。一旦客户端发送Over server 开始给出异常java.net.BindException: Address already in use。

即使我正在关闭套接字，为什么端口正在使用中？

标签： javasockets

以下代码行试图ServerSocket在端口上再次创建（实际上是无数次），5000这就是您收到错误的原因。

while (true) {
    try{
        server = new ServerSocket(port);

执行以下操作：

try{    
    server = new ServerSocket(port);    
}catch(IOException i){    
    System.out.println(i);
}   
while (true) {
    try{

java - BindException：地址已在使用中

问题描述

解决方案

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