java.net.SocketException : Connection reset by peer: socket write error When serving a file 异常

Question

我正在尝试使用套接字实现 HTTP 服务器。如果客户端(例如浏览器)请求目录，服务器会显示可用文件列表。当客户端请求文件时出现问题。我收到以下错误:

java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(SocketOutputStream.java:113)
at java.net.SocketOutputStream.write(SocketOutputStream.java:159)
at cf.charly1811.java.web.RequestHandler.writeFile(RequestHandler.java:152)
at cf.charly1811.java.web.RequestHandler.processRequest(RequestHandler.java:139)
at cf.charly1811.java.web.RequestHandler.handleRequest(RequestHandler.java:110)
at cf.charly1811.java.web.RequestHandler.run(RequestHandler.java:86)
at java.lang.Thread.run(Thread.java:745)

堆栈跟踪显示问题出在 writeFile() 方法中:

private void writeFile(File request) throws IOException 
{
    InputStream byteReader = new BufferedInputStream(new FileInputStream(request));
    byte[] buffer = new byte[1024];
    int bytesRead;
    while ((bytesRead = byteReader.read(buffer)) != -1) 
    {
        outputStream.write(buffer, 0, bytesRead);
    }
    byteReader.close();
}

但是我不知道哪里出了问题。你能帮帮我吗？

编辑

感谢大家的回答。在我阅读了您的回答后，我了解到问题出在 Socket 发生错误时。这是我的错误代码:

// Method to process a single request
handleRequest() throw IOException
{
    // process here
    // if the client request a file
    writeFile();
    // close socket when the request is processed
}

// The method is called
public run()
{
    try{
        // If an error occurs the try/catch won't be called because it is implemented outside the loop. So when an IOException occurs, the loop just stop and exit the program
        while(true)
        {
            handleRequest();
        }
    }
    catch(IOException e) {
        // Handle exception here
    }
}

我的新代码看起来像这样:

// Method to process a single request
handleRequest()
{
   try {
        // process here
        // if the client request a file
        writeFile();
        // close socket when the request is processed
    }
    // If this exception occurs the catch() method will be called
    catch(IOException e)
    {
        // handle exception here
    }
}

// The method is called
public run()
{
    while(true)
        {
            handleRequest();
        }
    }
}

Answer 1

TCP 套接字可能正在“关闭”而您的代码尚未收到通知。

这是生命周期的动画。 http://tcp.cs.st-andrews.ac.uk/index.shtml?page=connection_lifecycle

基本上，连接被客户端关闭了。您已经有了 throws IOException 和 SocketException extends IOException。这工作得很好。您只需要正确处理 IOException，因为它是 api 的正常部分。

编辑:RST 数据包在不存在或已关闭的套接字上接收到数据包时发生。您的应用程序没有区别。根据实现情况，reset 状态可能会持续，而 closed 永远不会正式发生。