AsyncTask和socket不能在android java中工作

Question

我正在java中制作一个简单的应用程序客户机-服务器，我希望我的手机接收和发送消息到我的pc，我在同一个LAN和我的pc的ip是192.168.1.8，我的serverSocket在端口7777上运行。出于某种原因，我的客户端android无法连接，我认为这是因为我在线程中创建了一个套接字，我已经读到我应该使用AsyncTask或Handle，我也尝试过，但我也得到了一个异常。

类服务器:

public class MyServer implements Runnable{

private ServerSocket server;
private ObjectInputStream in;
private ObjectOutputStream out;
private Socket clientedConnected;
public ExampleServerZNuC(){
    try {
        server= new ServerSocket(7777);
        System.out.println("server opened on port 7777");
    } catch (IOException ex) {
        Logger.getLogger(MyServer.class.getName()).log(Level.SEVERE, null, ex);
    }
}
public void sendMessage(String message){
    try {
        out.writeObject(message);
        out.flush();
    } catch (IOException ex) {
        Logger.getLogger(MyServer.class.getName()).log(Level.SEVERE, null, ex);
    }
}
public void sendNotifiy(){
  try {
        out.writeObject("Send Notify");
        out.flush();
    } catch (IOException ex) {
        Logger.getLogger(MyServer.class.getName()).log(Level.SEVERE, null, ex);
    }
}
public String getMessage(){
  return "";
}
public void run(){
    System.out.println("method run started");
    System.out.println("Waiting for a client to connect");
    try {
        Socket clientedConnected;
        clientedConnected = server.accept();
        System.out.println("A client connected : "+clientedConnected.getInetAddress().getHostAddress());
        in= new ObjectInputStream(clientedConnected.getInputStream());
        out = new ObjectOutputStream(clientedConnected.getOutputStream());


                } catch (IOException ex) {
        Logger.getLogger(MyServer.class.getName()).log(Level.SEVERE, null, ex);
    }
    System.out.println("End of method Run");
} }

这是我创建运行服务器时得到的输出:

 server opened on port 7777
 method run started
 Waiting for a client to connect

客户端android:类连接到我的服务器(ATM我只想让它接收消息):

 import java.io.IOException;
  import java.io.ObjectInputStream;
  import java.io.ObjectOutputStream;
  import java.io.OptionalDataException;
 import java.net.Socket;
 import java.net.UnknownHostException;
 import android.util.Log;
 import android.view.View;
 import android.widget.TextView;
public class MyConnect implements Runnable{
private Socket myconnect=null ;
private TextView txtMessage;
private ObjectInputStream in; 
private ObjectOutputStream out;
public MyConnect( ){
    try {
        // this is my pc's IP, my phone is connected to same LAN
        Log.d("inizializating socket","");
        myconnect= new Socket("192.168.1.8",7777);
        in = new ObjectInputStream(myconnect.getInputStream());
        out = new ObjectOutputStream(myconnect.getOutputStream());
    } catch (UnknownHostException e) {
        Log.d("My Error connecting",e.getMessage());
    } catch (IOException e) {
        Log.d("My Error connecting",e.getMessage());
    }
 }
 @Override
 public void run() {
        try {
            String message = (String)in.readObject();
            Log.d("messaged recived",message);
        } catch (OptionalDataException e) {             
            Log.d("My Error connecting",e.getMessage());
        } catch (ClassNotFoundException e) {
            Log.d("Error My ClassNotFoundException",e.getMessage());
        } catch (IOException e) {
            Log.d("Error My IOEXCEPTION",e.getMessage());
        }


  }
 }

这是当我点击一个应该创建套接字的按钮时得到的错误:on create i use connect= new MyConnect();对于onclick事件，我使用:

   @Override
   public void onClick(View v) {
    switch(v.getId()){
    case R.id.btnExample:

        new Thread(connect).start();
        break;

    }
}

错误提示:

05-29 19:02:05.905: E/AndroidRuntime(6520): FATAL EXCEPTION: main
05-29 19:02:05.905: E/AndroidRuntime(6520):      android.os.NetworkOnMainThreadException
05-29 19:02:05.905: E/AndroidRuntime(6520):     at android.os.StrictMode$AndroidBlockGuardPolicy.onNetwork(StrictMode.java:1118)
05-29 19:02:05.905: E/AndroidRuntime(6520):     at  libcore.io.BlockGuardOs.connect(BlockGuardOs.java:84)
05-29 19:02:05.905: E/AndroidRuntime(6520):     at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
05-29 19:02:05.905: E/AndroidRuntime(6520):     at libcore.io.IoBridge.connect(IoBridge.java:112)
05-29 19:02:05.905: E/AndroidRuntime(6520):     at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
 05-29 19:02:05.905: E/AndroidRuntime(6520):    at    java.net.PlainSocketImpl.connect(PlainSocketImpl.java:172)
05-29 19:02:05.905: E/AndroidRuntime(6520):     at java.net.Socket.startupSocket(Socket.java:566)
05-29 19:02:05.905: E/AndroidRuntime(6520):     at java.net.Socket.tryAllAddresses(Socket.java:127)

编辑:

class MySyncTask extends AsyncTask<Integer, Integer, String>{
    String advice;
@Override
protected String doInBackground(Integer... params) {
    try {
        s = new Socket("192.168.1.8",7777);
        Log.d("socket connected","");
         ObjectInputStream streamReader = new ObjectInputStream(s.getInputStream()); 
            advice = (String)streamReader.readObject();
    } catch (UnknownHostException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
        return "";
    }
protected void onPostExecute(String result) {
     txtMessage.setText("you got a message: " + advice);
}
protected void onPreExecute() {
   Log.d("my started","start");
}    
}

，我用了

  MySyncTask asyncTask=new MySyncTask ();
     asyncTask.execute();

on onCreate()方法，但由于某种原因，它没有连接到我的服务器

LogCat with AsyncTask:

05-29 19:46:21.900: D/my started(26169): start
05-29 19:46:22.020: D/libEGL(26169): loaded /system/lib/egl/l ibEGL_mali.so
05-29 19:46:22.030: D/libEGL(26169): loaded /system/lib/egl/libGLESv1_CM_mali.so
05-29 19:46:22.040: D/libEGL(26169): loaded /system/lib/egl/libGLESv2_mali.so
05-29 19:46:22.080: D/OpenGLRenderer(26169): Enabling debug mode 0

编辑问题解决

在互联网上搜索为什么套接字没有连接后，我发现有人有类似的问题，我在这里找到了Android套接字没有被实例化的答案我必须先初始化套接字，然后使用connect

Answer 1

发生这种情况是因为您试图在主线程上执行网络操作。这是糟糕的设计，您不希望在运行可能需要很长时间才能执行的进程时锁定用户界面。

把你的网络方法放在AsyncTask或Service中。

 private class DownloadFilesTask extends AsyncTask<URL, Integer, Long> {
     protected Long doInBackground(URL... urls) {
         int count = urls.length;
         long totalSize = 0;
         for (int i = 0; i < count; i++) {
             totalSize += Downloader.downloadFile(urls[i]);
             publishProgress((int) ((i / (float) count) * 100));
             // Escape early if cancel() is called
             if (isCancelled()) break;
         }
         return totalSize;
     }
     protected void onProgressUpdate(Integer... progress) {
         setProgressPercent(progress[0]);
     }
     protected void onPostExecute(Long result) {
         showDialog("Downloaded " + result + " bytes");
     }
 }

Answer 2

正如Eduardo指出的，

NetworkOnMainThreadException

当应用程序试图执行在其主线程上进行网络操作。

使用Asynctask连接

一定要有

<uses-permission android:name="android.permission.INTERNET" /> 

放入AndroidManifest.xml

Answer 3

您是否在清单中设置了适当的权限?如果是，手机和你的电脑在同一个网络上吗(如果他们在同一个wifi网络上是好的)?尝试运行调试器并设置断点。

这是一个很好的教程，解释了客户端/服务器通信在android。http://examples.javacodegeeks.com/android/core/socket-core/android-socket-example/

好运拉