安卓 java。网AsyncTask中的ConnectionException

Question

我收到了一个“java”。网我的安卓应用程序的AsyncTask中存在ConnectionException，我不完全确定原因

除此之外，我还收到以下两个相关错误：

04-26 16:24:20.339  20501-20514/com1032.cw1.ct00162.ct00162_todolist       W/System.err﹕ at          com1032.cw1.ct00162.ct00162_todolist.RetrieveFeed.doInBackground(RetrieveFeed.java:45)
04-26 16:24:20.339  20501-20514/com1032.cw1.ct00162.ct00162_todolist  W/System.err﹕ at   com1032.cw1.ct00162.ct00162_todolist.RetrieveFeed.doInBackground(RetrieveFeed.ja va:18)

下面是我的AsyncTask中的代码

这里是我的第二个错误出现的地方：

public class RetrieveFeed extends AsyncTask<Void, Void, JSONObject>{

JSONObject mainObject = null;
String sql = null;
String URL_TO_PHP = "http://192.168.0.102//todo_gate.php?qe=";
MainActivity c = null;

public RetrieveFeed(String sql){
    this.sql = sql;
}

public RetrieveFeed(MainActivity ma){
    this.c = ma;
    this.sql = "SELECT * FROM todoloist01";
}

@Override
protected JSONObject doInBackground(Void... params) {

    try {

        URL url = new URL(URL_TO_PHP+sql);
        URLConnection UrlC = url.openConnection();
        BufferedReader in = new BufferedReader(
                new InputStreamReader(

第一个错误出现在这里：

                       UrlC.getInputStream()));

        String r = in.readLine();
        mainObject = new JSONObject(r);

     } catch (Exception e) {
        e.printStackTrace();
        Log.i("CONNECTION ","Failed");
    }


    return mainObject;
}

@Override
protected void onPostExecute(JSONObject result) {
    super.onPostExecute(result);
    if(result != null){
        Log.i("JSON RETURN",result.toString());
        c.js = result;
    }
    else
       Log.i("JSON RETURN","Null return");



}

}

我的全部例外：

    04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist   W/System.err﹕ java.net.ConnectException: failed to connect to /192.168.0.102   (port 80): connect failed: EHOSTUNREACH (No route to host)
    04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist  W/System.err﹕ at libcore.io.IoBridge.connect(IoBridge.java:114)
    04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:192)
    04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.net.PlainSocketImpl.connect(PlainSocketImpl.java:459)
    04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.net.Socket.connect(Socket.java:843)
    04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at   com.安卓.okhttp.internal.Platform.connectSocket(Platform.java:131)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com.安卓.okhttp.Connection.connect(Connection.java:101)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist  W/System.err﹕ at   com.安卓.okhttp.internal.http.HttpEngine.connect(HttpEngine.java:294)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com.安卓.okhttp.internal.http.HttpEngine.sendSocketRequest(HttpEngine.java:25 5)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com.安卓.okhttp.internal.http.HttpEngine.sendRequest(HttpEngine.java:206)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com.安卓.okhttp.internal.http.HttpURLConnectionImpl.execute(HttpURLConnectionImpl.java:345)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com.安卓.okhttp.internal.http.HttpURLConnectionImpl.getResponse(HttpURLConnectionImpl.java:296)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com.安卓.okhttp.internal.http.HttpURLConnectionImpl.getInputStream(HttpURLConnectionImpl.java:179)
   04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com1032.cw1.ct00162.ct00162_todolist.RetrieveFeed.doInBackground(RetrieveFeed.java:43)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at com1032.cw1.ct00162.ct00162_todolist.RetrieveFeed.doInBackground(RetrieveFeed.java:18)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at 安卓.os.AsyncTask$2.call(AsyncTask.java:288)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.util.concurrent.FutureTask.run(FutureTask.java:237)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at 安卓.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:231)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1112)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:587)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at java.lang.Thread.run(Thread.java:841)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ Caused by: libcore.io.ErrnoException: connect failed: EHOSTUNREACH (No route to host)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at libcore.io.Posix.connect(Native Method)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at libcore.io.BlockGuardOs.connect(BlockGuardOs.java:85)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at libcore.io.IoBridge.connectErrno(IoBridge.java:127)
  04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist W/System.err﹕ at libcore.io.IoBridge.connect(IoBridge.java:112)
       04-26 16:59:18.428  22925-22942/com1032.cw1.ct00162.ct00162_todolist  W/System.err﹕ ... 19 more