Java tutorial
/******************************************************************************* * Copyright (C) 2014-2015 Artem Yankovskiy (artemyankovskiy@gmail.com). * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. ******************************************************************************/ package ru.neverdark.phototools.azimuth.model; import android.content.Context; import android.net.ConnectivityManager; import android.net.NetworkInfo; import com.google.android.gms.maps.model.LatLng; import org.apache.http.HttpEntity; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.StatusLine; import org.apache.http.client.HttpClient; import org.apache.http.client.methods.HttpGet; import org.apache.http.impl.client.DefaultHttpClient; import org.apache.http.params.BasicHttpParams; import org.apache.http.params.HttpConnectionParams; import org.apache.http.params.HttpParams; import org.json.JSONArray; import org.json.JSONException; import org.json.JSONObject; import java.io.BufferedReader; import java.io.InputStream; import java.io.InputStreamReader; import java.io.UnsupportedEncodingException; import java.net.URLEncoder; import ru.neverdark.phototools.azimuth.utils.Log; public class Geocoder { private Context mContext; /** * Constructor * * @param context application context */ public Geocoder(Context context) { mContext = context; } /** * Gets coordinate from location name * * @param searchString user specify location name * @return coordinates for founded location or null if not found */ public LatLng getFromLocation(String searchString) { LatLng coords = null; String locationInfo = getLocationInfo(searchString); if (locationInfo.length() > 0) { try { JSONObject jsonObject = new JSONObject(locationInfo); JSONArray jsonArray = (JSONArray) jsonObject.get("results"); JSONObject jsonLocation = jsonArray.getJSONObject(0).getJSONObject("geometry") .getJSONObject("location"); Double longitude = jsonLocation.getDouble("lng"); Double latitude = jsonLocation.getDouble("lat"); coords = new LatLng(latitude, longitude); } catch (JSONException e) { e.printStackTrace(); } } return coords; } /** * Gets json for location * * @param searchString location for search * @return json for location or empty string if connection problem */ private String getLocationInfo(String searchString) { String query = null; try { query = URLEncoder.encode(searchString, "UTF-8"); } catch (UnsupportedEncodingException e1) { // TODO Auto-generated catch block e1.printStackTrace(); } String url = String.format("http://maps.google.com/maps/api/geocode/json?address=%s&sensor=false", query); StringBuilder builder = new StringBuilder(); HttpParams params = new BasicHttpParams(); HttpConnectionParams.setConnectionTimeout(params, 4000); // 4 sec HttpConnectionParams.setSoTimeout(params, 1000); // 1 sec HttpClient client = new DefaultHttpClient(params); HttpGet httpGet = new HttpGet(url); httpGet.setParams(params); try { HttpResponse response = client.execute(httpGet); StatusLine statusLine = response.getStatusLine(); int statusCode = statusLine.getStatusCode(); if (statusCode == HttpStatus.SC_OK) { HttpEntity entity = response.getEntity(); InputStream content = entity.getContent(); BufferedReader reader = new BufferedReader(new InputStreamReader(content)); String line; while ((line = reader.readLine()) != null) { builder.append(line); } } else { Log.message("Download fail"); } } catch (Exception e) { // request new address for object // creating new object is a faster then setLength(0) builder = new StringBuilder(); } return builder.toString(); } /** * Checks connection status * * @return true if device online, false in other case */ public boolean isOnline() { ConnectivityManager cm = (ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE); NetworkInfo netInfo = cm.getActiveNetworkInfo(); if (netInfo != null && netInfo.isConnected()) { return true; } return false; } }