为什么Android中的HTTPost在JSP页面上给我null？

Question

我正在构建一个应用程序，用于跟踪具有纬度和经度的用户。必须将此纬度和经度发布到服务器。

我构建了一个服务，以便它为用户提供当前位置。

这是我的代码：

MYService.java

package com.example.rama.locationtracking;

/**
 * Created by RAMA on 4/10/2016.
 */

public class MyService extends Service {
    private static final String TAG = "SRI";
    private LocationManager mLocationManager = null;
    private static final int LOCATION_INTERVAL = 1000;
    private static final float LOCATION_DISTANCE = 0;
    private double Longitude,Latitude;
    private static String url ="http://49.206.9.182:8080/ezomart/latlong.jsp";
    private String latitude_str;
    private String longitude_str;


    private class LocationListener implements android.location.LocationListener {
        Location mLastLocation;


        public LocationListener(String provider) {
            Log.e(TAG, "LocationListener " + provider);
            mLastLocation = new Location(provider);
        }

        @Override
        public void onLocationChanged(Location location) {
            Log.e(TAG, "onLocationChanged: " + location);
            Longitude = location.getLongitude();
            Latitude = location.getLatitude();
            postToWebServer(Longitude,Latitude);
            mLastLocation.set(location);
        }

        @Override
        public void onProviderDisabled(String provider) {
            Log.e(TAG, "onProviderDisabled: " + provider);
        }

        @Override
        public void onProviderEnabled(String provider) {
            Log.e(TAG, "onProviderEnabled: " + provider);
        }

        @Override
        public void onStatusChanged(String provider, int status, Bundle extras) {
            Log.e(TAG, "onStatusChanged: " + provider);
        }
    }

    private void postToWebServer(double longitude, double latitude)
    {
        latitude_str = String.valueOf(latitude);
        longitude_str = String.valueOf(longitude);

        Log.e(TAG,latitude_str);
        Log.e(TAG, longitude_str);


        new Thread(new Runnable() {
            @Override
            public void run()
            {
                HttpClient httpClient = new DefaultHttpClient();

        HttpPost httpPost = new HttpPost("http://49.206.9.182:8080/ezomart/latlong.jsp");


        //Post Data
        List<NameValuePair> nameValuePair = new ArrayList<NameValuePair>(2);
        nameValuePair.add(new BasicNameValuePair("userName", latitude_str));
        nameValuePair.add(new BasicNameValuePair("password", longitude_str));


        //Encoding POST data
        try {
            httpPost.setEntity(new UrlEncodedFormEntity(nameValuePair));
        } catch (UnsupportedEncodingException e) {
            // log exception
            e.printStackTrace();
        }

        //making POST request.
        try {
            HttpResponse response = httpClient.execute(httpPost);
            // write response to log
            String responseBody = EntityUtils.toString(response.getEntity());
//            Log.d("Http Post Response:", responseBody);
        } catch (ClientProtocolException e) {
            // Log exception
            e.printStackTrace();
        } catch (IOException e) {
            // Log exception
            e.printStackTrace();
        }

            }
        }).start();
    }


    LocationListener[] mLocationListeners = new LocationListener[]{
            new LocationListener(LocationManager.GPS_PROVIDER),
            new LocationListener(LocationManager.NETWORK_PROVIDER)
    };

    @Override
    public IBinder onBind(Intent arg0) {
        return null;
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.e(TAG, "onStartCommand");
        super.onStartCommand(intent, flags, startId);
        return START_STICKY;
    }

    @Override
    public void onCreate() {
        Log.e(TAG, "onCreate");
        initializeLocationManager();
//        makePostRequestOnNewThread();
        try {
            mLocationManager.requestLocationUpdates(
                    LocationManager.NETWORK_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
                    mLocationListeners[1]);
        } catch (java.lang.SecurityException ex) {
            Log.i(TAG, "fail to request location update, ignore", ex);
        } catch (IllegalArgumentException ex) {
            Log.d(TAG, "network provider does not exist, " + ex.getMessage());
        }
        try {
            mLocationManager.requestLocationUpdates(
                    LocationManager.GPS_PROVIDER, LOCATION_INTERVAL, LOCATION_DISTANCE,
                    mLocationListeners[0]);
        } catch (java.lang.SecurityException ex) {
            Log.i(TAG, "fail to request location update, ignore", ex);
        } catch (IllegalArgumentException ex) {
            Log.d(TAG, "gps provider does not exist " + ex.getMessage());
        }
    }


    @Override
    public void onDestroy() {
        Log.e(TAG, "onDestroy");
        super.onDestroy();
        if (mLocationManager != null) {
            for (int i = 0; i < mLocationListeners.length; i++) {
                try {
                    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
                        // TODO: Consider calling
                        //    ActivityCompat#requestPermissions
                        // here to request the missing permissions, and then overriding
                        //   public void onRequestPermissionsResult(int requestCode, String[] permissions,
                        //                                          int[] grantResults)
                        // to handle the case where the user grants the permission. See the documentation
                        // for ActivityCompat#requestPermissions for more details.
                        return;
                    }
                    mLocationManager.removeUpdates(mLocationListeners[i]);
                } catch (Exception ex) {
                    Log.i(TAG, "fail to remove location listners, ignore", ex);
                }
            }
        }
    }

    private void initializeLocationManager() {
        Log.e(TAG, "initializeLocationManager");
        if (mLocationManager == null) {
            mLocationManager = (LocationManager) getApplicationContext().getSystemService(Context.LOCATION_SERVICE);
        }
    }
}

MainActivity.java

@Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        Toolbar toolbar = (Toolbar) findViewById(R.id.toolbar);
        setSupportActionBar(toolbar);


        startService(new Intent(this, MyService.class));

    }

JSP代码

<%@page contentType="text/html" pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html>
    <head>
        <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
        <title>JSP Page</title>
    </head>
    <body>
        <%
String lat=request.getParameter("userName");        
String longg=request.getParameter("password");
%>
        <h1>Hello World!</h1>
        <%=lat%>, <%=longg%>
    </body>
</html>