Question

在我的Android应用中，我尝试连接到本地服务器上的端口以获取一些数据包。我已经尝试了一些代码和代码。赶上，但使用以下代码：

address = "192.168.175.82";
public void run() {
    try {
  smtpSocket = new Socket(address, 60001);

        os = new DataOutputStream(smtpSocket.getOutputStream());
        is = new DataInputStream(smtpSocket.getInputStream());
    } catch (UnknownHostException e) {
        System.err.println("Don't know about host: " + address);
        run();
    } catch (IOException e) {
        System.err.println("Couldn't get I/O for the connection to: " + address);
        run();
    } catch (Exception e) {
     System.out.println("retry");
     run();
    }

如果服务器没有打开，我显然会在出现堆栈溢出错误并且应用程序崩溃之前几次（例如几百次）获得IOException。

01-20 22:21:32.526: ERROR/AndroidRuntime(5678): java.lang.StackOverflowError
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.util.Hashtable.get(Hashtable.java:282)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.util.Properties.getProperty(Properties.java:177)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.lang.System.getProperty(System.java:440)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.lang.System.getProperty(System.java:412)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.lang.Boolean.getBoolean(Boolean.java:174)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at org.apache.harmony.luni.net.NetUtil$Action.run(NetUtil.java:89)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at org.apache.harmony.luni.net.NetUtil$Action.run(NetUtil.java:80)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.security.AccessController.doPrivilegedImpl(AccessController.java:264)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.security.AccessController.doPrivileged(AccessController.java:84)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at org.apache.harmony.luni.net.NetUtil.preferIPv6Addresses(NetUtil.java:51)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at org.apache.harmony.luni.net.PlainSocketImpl.bind(PlainSocketImpl.java:190)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.net.Socket.startupSocket(Socket.java:777)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.net.Socket.tryAllAddresses(Socket.java:192)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.net.Socket.<init>(Socket.java:256)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at java.net.Socket.<init>(Socket.java:220)
01-20 22:21:32.526: ERROR/AndroidRuntime(5678):     at com.example.sockets.ReadSocket.run(ReadSocket.java:83)

有谁能请我指出如何使其发挥作用的正确方向？也许我应该先以某种方式测试连接（如果是这样，请说明怎么做？）感谢

克里斯

Answer 1

对于初学者，请删除递归调用。这将摆脱堆栈溢出。用循环替换它并在每次不成功的迭代中休眠

  public void run() {
     boolean connected = false;  
     while(!connected)
     {
     try {
      smtpSocket = new Socket(address, 60001);

            os = new DataOutputStream(smtpSocket.getOutputStream());
            is = new DataInputStream(smtpSocket.getInputStream());


      connected = true;
    } catch (UnknownHostException e) {
        System.err.println("Don't know about host: " + address);

    } catch (IOException e) {
        System.err.println("Couldn't get I/O for the connection to: " + address);

        } catch (Exception e) {
         System.out.println("retry");

        }
        if (!connected)
            Thread.sleep(1000)
      }
    }

Answer 2

您可以在套接字上尝试isConnected()和isBound()，以便在尝试获取输入流之前检查您是否已连接。

Android网络编程：IOExceptions和StackOverflowError

2 个答案: