java - 如何修复 Broken Pipe Socket 异常 (Java)？连接在哪里被关闭？

Question

我正在为一个学校项目开发一个多线程网络服务器。我应该能够在浏览器上进入本地主机并请求 3 个不同的文件(.htm、.jpeg、.pdf)。但是，当我对其中包含图片的 .htm 文件执行此操作(2 个请求)时，.htm 文件会出现在浏览器中，但对于我尝试在图片上执行的每次写入，都会出现许多损坏的管道套接字异常(分配需要一次写入 1024 个字节)。我实现此方法的方式明显有问题，但当我尝试写入第二个文件时，我不知道连接在哪里关闭？

我尝试了一些不同的方法来尝试解决此问题，包括尝试读取套接字输入流时的循环，但我认为这违背了多线程服务器的目的。

服务器:

    while(true){
        try {
            sock = servSock.accept(); // Handles the connection
            // Connection received log
            System.out.println("Connection received: " + new Date().toString() + " at " + sock.getInetAddress() + sock.getPort());
            HTTP pro = new HTTP(sock); // Client handler
            pro.run();

            ServerThread serverThread = new ServerThread(pro); 
            // Starts ServerThread
            serverThread.start();
        } catch (Exception e){
            System.out.println(e);
        }
    }

HTTP:

    public void run(){
        // Try to open reader
        try{
            readSock = new BufferedReader(new InputStreamReader(sock.getInputStream()));
        } catch (Exception e){
            System.out.println(e);
        }

        // Open output stream
        try{
            this.out = new DataOutputStream(sock.getOutputStream()); 
            this.printOut = new PrintWriter(sock.getOutputStream()); 
        } catch (Exception e){
            System.out.println(e);
        }

        // Try to read incoming line
        try {
            this.reqMes = readSock.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }

        StringTokenizer st = new StringTokenizer(reqMes);

        // Parse the request message
        int count = 0;
        while(st.hasMoreTokens()){
            String str = st.nextToken();
            if (count == 1){
                this.fileName = "." + str;
            }
            count += 1;
        }
        System.out.println("File name received.");

        File file = null;
        try {
            file = new File(this.fileName);
            this.f = new FileInputStream(file); // File input stream
            this.fileExists = true;
            System.out.println("File " + this.fileName +  " exists.");
        } catch (FileNotFoundException e) {
            System.out.println(e);
            this.fileExists = false;
            System.out.println("File does not exist.");
        }

        byte[] buffer = new byte[1024];
        // Write status line
        if (this.fileExists) {
            System.out.println("Trying to write data");
            try{
                this.out.writeBytes("HTTP/1.0 " + "200 OK " + this.CRLF);
                this.out.flush();
                this.printOut.println("HTTP/1.0 " + "200 OK " + this.CRLF);
                // Write Header
                this.out.writeBytes("Content-type: " + getMime(this.fileName) + this.CRLF);
                this.printOut.println("Content-type: " + getMime(this.fileName) + this.CRLF);
                this.out.flush();

                // Read file data
                byte[] fileData = new byte[1024];

                while (this.f.read(fileData) != -1) {
                    // Write File data
                    try{
                        this.out.write(fileData,0,1024);
                        this.out.flush(); // Flush output stream
                    } catch (IOException e) {
                        System.out.println(e);
                    }
                }
                System.out.println("Flushed");
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

对于浏览器中的一个 .htm 文件，该文件和 html 看起来都很好。但看起来它在 html 文件中对 .jpeg 文件发出了第二个请求，并且浏览器在每次写入数据时都卡住了 java.net.SocketException: Broken pipeline (Write failed) 加载

this.out.write(fileData,0,1024);

谢谢，非常感谢您的帮助。

Answer 1

经过对不同问题的大量搜索，我找到了答案 here .

问题在于响应 header 格式不正确，导致连接过早结束。 必须在 header 之后发送另一个空行(“\r\n”)。

以下代码现在可以运行(this.CRLF 等于“\r\n”):

    public void run(){
        // Try to open reader
        try{
            readSock = new BufferedReader(new InputStreamReader(sock.getInputStream()));
        } catch (Exception e){
            System.out.println(e);
        }

        // Open output stream
        try{
            this.out = new DataOutputStream(sock.getOutputStream()); // Data output
            this.printOut = new PrintWriter(sock.getOutputStream()); // Print output
        } catch (Exception e){
            System.out.println(e);
        }

        // Try to read incoming line
        try {
            this.reqMes = readSock.readLine();
        } catch (IOException e) {
            e.printStackTrace();
        }

        StringTokenizer st = new StringTokenizer(reqMes);

        // Parse the request message
        int count = 0;
        while(st.hasMoreTokens()){
            String str = st.nextToken();
            if (count == 1){
                this.fileName = "." + str;
            }
            count += 1;
        }
        System.out.println("File name received.");

        // Initialize file to be sent
        File file = null;
        // Try to find file and create input stream
        try {
            file = new File(this.fileName);
            this.f = new FileInputStream(file); // File input stream
            this.fileExists = true;
            System.out.println("File " + this.fileName +  " exists.");
        } catch (FileNotFoundException e) {
            System.out.println(e);
            this.fileExists = false;
            System.out.println("File does not exist.");
        }

        byte[] buffer = new byte[1024];
        // Write status line
        if (this.fileExists) {
            System.out.println("Trying to write data");
            try{
                this.out.writeBytes("HTTP/1.0 " + "200 OK " + this.CRLF);
                this.out.flush();
                // Write Header
                this.out.writeBytes("Content-type: " + getMime(this.fileName) + this.CRLF);
                this.out.flush();
                this.out.writeBytes(this.CRLF);
                this.out.flush();

                // Read file data
                byte[] fileData = new byte[1024];

                int i;
                while ((i = this.f.read(fileData)) > 0) {
                    // Write File data
                    try{
                        this.out.write(fileData,0, i);
                    } catch (IOException e) {
                        System.out.println(e);
                    }
                }
                this.out.flush(); // Flush output stream
                System.out.println("Flushed");
                closeSock(); // Closes socket
            } catch (IOException e) {
                e.printStackTrace();
            }