Question

我正在创建一个NetUtils类，该类扩展线程以处理GUI中的套接字通信而不会阻塞主线程。我的代码如下所示（假设所有导入都被考虑在内）：

主要方法

public static void main(String[] args) {
    EventQueue.invokeLater( () -> {
         new Window().setVisible(true);
    });
}

窗口类

public class Window { // normally would extend JFrame bc this is a gui
    // ...
    NetUtils comms;

    public Window() {
        // ...
        comms = new NetUtils("192.168.1.1", 288); // this ip/port info works fine
        comms.start();
        // ...
    }

    // other methods....
}

NetUtils类

public class NetUtils extends Thread {
    private String ip;
    private int port;

    public NetUtils(String ip, int port) {
        this.ip = ip;
        this.port = port;
    }

    @Override
    public void run() {
        try (Socket socket = new Socket()) {
            socket.connect(new InetSocketAddress(ip, port), 10000); // timeout 10s
            System.out.println("Socket started: " + socket); // correctly prints

            while (true) { // during the life of the thread
                String line = readLine(socket); // throws SocketException here (socket closed error)
                System.out.println(line);
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    private String readLine(Socket socket) {
        // uses inputstream to read bytes and such
        String line;
        boolean isDone = false;
        while (!isDone) {
            try (InputStreamReader isr = new InputStreamReader(socket.getInputStream))) {
                if (isr.ready()) {
                    line += (char) isr.read();
                }
                if (!isr.ready() && line != "") {
                    isDone = true;
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
        return line;
    }
}

我在做什么会导致套接字关闭？我直接在main方法中运行NetUtils代码（我没有将readLine方法分开），它按照我的预期运行，这让我相信问题与套接字在线程中有关。谢谢你的帮助。

Answer 1

显然＆＃39;这部分有效＆＃39;正在关闭套接字或其输入或输出流。

注意：您没有在发布的代码中检查流的结尾。我不认为需要readLine()方法。只需用以下代码替换你的循环：

BufferedReader reader = new BufferedReader(new InputStreamReader(socket.getInputStream()));
String line;
while ((line = reader.readLine()) != null)
{
    System.out.println(line);
}
reader.close();

[省略异常处理。]

套接字在创建后立即关闭

1 个答案: