将Android设备连接到PC时异常连接被拒绝

Question

This i the code of Connection

  protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    DL_URL = "http://localhost:8080/project-server/rest/?value=test";
    downloadJsonFile();

}

 private void downloadJsonFile() {
        try {
            createFileAndDirectory();
            URL url = new URL(DL_URL);
            HttpURLConnection urlConnection;
            urlConnection = (HttpURLConnection) url.openConnection();
            urlConnection.setRequestMethod("GET");
            urlConnection.setDoOutput(true);
            urlConnection.connect();


            int status = urlConnection.getResponseCode();

            Log.v("gg", Integer.toString(status));
            if (status == HttpURLConnection.HTTP_OK) {
            FileOutputStream fileOutput = new FileOutputStream(jsonFile);
            InputStream inputStream = urlConnection.getInputStream();
            byte[] buffer = new byte[1024];
            int bufferLength = 0;
            while ((bufferLength = inputStream.read(buffer)) > 0) {
            fileOutput.write(buffer, 0, bufferLength);
            }
            fileOutput.close();
            }else{
                 Toast.makeText(MainActivity.this,"error :)", Toast.LENGTH_LONG).show();

        }} catch (MalformedURLException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

        }

And this is my servles located @my own PC tha I try to connect to it (I use Windows 7)

   protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    doPost(request, response);
}

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {

 }

Erros I get

    06-18 12:42:55.940: W/System.err(4740): java.net.ConnectException: localhost/127.0.0.1:8080 - Connection refused
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:207)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.net.PlainSocketImpl.connect(PlainSocketImpl.java:437)
    06-18 12:42:55.950: W/System.err(4740):     at java.net.Socket.connect(Socket.java:983)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>(HttpConnection.java:75)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection.<init>(HttpConnection.java:48)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnection$Address.connect(HttpConnection.java:322)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpConnectionPool.get(HttpConnectionPool.java:89)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.getHttpConnection(HttpURLConnectionImpl.java:285)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.makeConnection(HttpURLConnectionImpl.java:267)
    06-18 12:42:55.950: W/System.err(4740):     at org.apache.harmony.luni.internal.net.www.protocol.http.HttpURLConnectionImpl.connect(HttpURLConnectionImpl.java:205)
    06-18 12:42:55.950: W/System.err(4740):     at com.example.test1.MainActivity.downloadJsonFile(MainActivity.java:42)
    06-18 12:42:55.950: W/System.err(4740):     at com.example.test1.MainActivity.onCreate(MainActivity.java:30)
    06-18 12:42:55.950: W/System.err(4740):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1047)
    06-18 12:42:55.950: W/System.err(4740):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:1722)
    06-18 12:42:55.950: W/System.err(4740):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:1784)
    06-18 12:42:55.950: W/System.err(4740):     at android.app.ActivityThread.access$1500(ActivityThread.java:123)
    06-18 12:42:55.950: W/System.err(4740):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:939)
    06-18 12:42:55.950: W/System.err(4740):     at android.os.Handler.dispatchMessage(Handler.java:99)
    06-18 12:42:55.950: W/System.err(4740):     at android.os.Looper.loop(Looper.java:130)
    06-18 12:42:55.950: W/System.err(4740):     at android.app.ActivityThread.main(ActivityThread.java:3835)
    06-18 12:42:55.950: W/System.err(4740):     at java.lang.reflect.Method.invokeNative(Native Method)
    06-18 12:42:55.950: W/System.err(4740):     at java.lang.reflect.Method.invoke(Method.java:507)
    06-18 12:42:55.950: W/System.err(4740):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:864)
    06-18 12:42:55.950: W/System.err(4740):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:622)
    06-18 12:42:55.960: W/System.err(4740):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

You are trying to access http://localhost:8080/project-server/rest/?value=test , but localhost refers to the loopback address 127.0.0.1, so your request is sent to your Android device itself, not to your pc. Change localhost with the ip address of your pc.

Answer 2

Try to connect using "10.0.2.2:8080" instead of using "localhost:8080"

It'll work...