it.smartcampuslab.riciclo.geo.OSMGeocoder.java Source code

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Here is the source code for it.smartcampuslab.riciclo.geo.OSMGeocoder.java

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/*******************************************************************************
 * Copyright 2012-2013 Trento RISE
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *        http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either   express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 ******************************************************************************/
package it.smartcampuslab.riciclo.geo;

import java.io.IOException;
import java.net.ProtocolException;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Locale;
import java.util.Map;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import eu.trentorise.smartcampus.network.RemoteConnector;
import eu.trentorise.smartcampus.network.RemoteException;

/**
 * Geocoder based on the SC geocoder Web service.
 * Performs the operations of direct/reverse geocoding.
 * @author raman
 *
 */
public class OSMGeocoder {

    /**
     * 
     */
    private static final double GEOCODE_DISTANCE = 0.5d;
    private Context mContext;
    private Locale mLocale = Locale.getDefault();

    private static final String LOC_PATH = "/core.geocoder/spring/location";
    private static final String ADDR_PATH = "/core.geocoder/spring/address";
    private String serverUrl;

    /**
     * Constructor based on the specified server address
     * @param context
     * @param serverUrl
     */
    public OSMGeocoder(Context context) {
        this(context, "https://vas.smartcampuslab.it", Locale.getDefault());
    }

    /**
     * Constructor based on the specified server address and locale
     * @param context
     * @param serverUrl
     * @param locale
     */
    public OSMGeocoder(Context context, String serverUrl, Locale locale) {
        mContext = context;
        mLocale = locale;
        this.serverUrl = serverUrl;
    }

    private boolean isConnected() {
        NetworkInfo info = ((ConnectivityManager) mContext.getSystemService(Context.CONNECTIVITY_SERVICE))
                .getActiveNetworkInfo();
        return info != null && info.isConnected();
    }

    private List<OSMAddress> queryLocations(String q, double[] referenceLocation, Double radius, String token)
            throws RemoteException, Exception, ProtocolException {

        List<OSMAddress> addrs = null;
        if (!isConnected())
            throw new Exception("No connection");

        try {
            StringBuilder sb = new StringBuilder();
            if (q != null) {
                sb.append(ADDR_PATH);
            } else {
                sb.append(LOC_PATH);
            }
            Map<String, Object> params = new HashMap<String, Object>();
            params.put("latlng", referenceLocation[0] + "," + referenceLocation[1]);
            params.put("distance", radius);
            if (q != null) {
                params.put("address", q);
            }

            JSONObject jsonObject = execute(serverUrl, sb.toString(), params, token);

            addrs = jsonObject2addressList(jsonObject);
            return addrs;
        } catch (IOException e) {
            throw new ProtocolException(e.getMessage());
        } catch (JSONException e) {
            throw new ProtocolException(e.getMessage());
        }

    }

    /**
     * Reverse geocoding operation. Cannot be called from UI thread.
     * @param lat
     * @param lng
     * @param token access token
     * @return list of {@link OSMAddress} instances around the 
     * specified point ordered by the increasing distance to the point
     */
    public List<OSMAddress> getFromLocation(double lat, double lng, String token)
            throws ProtocolException, RemoteException, Exception {
        if (!isConnected())
            throw new Exception("No connection");

        return queryLocations(null, new double[] { lat, lng }, GEOCODE_DISTANCE, token);
    }

    private List<OSMAddress> jsonObject2addressList(JSONObject in) throws IOException, JSONException {
        List<OSMAddress> addrs = new ArrayList<OSMAddress>();

        JSONObject jsonObject = in.getJSONObject("response");

        JSONArray results = jsonObject.getJSONArray("docs");
        if (results == null || results.length() < 1) {
            return addrs;
        }

        for (int i = 0; i < results.length(); i++) {
            JSONObject a = results.getJSONObject(i);
            OSMAddress address = new OSMAddress(mLocale, a);
            addrs.add(address);
        }

        return addrs;
    }

    private JSONObject execute(String server, String query, Map<String, Object> params, String token)
            throws SecurityException, RemoteException {
        String result = RemoteConnector.getJSON(server, query, token, params);
        JSONObject jsonObject = new JSONObject();
        try {
            jsonObject = new JSONObject(result);
        } catch (JSONException e) {
            e.printStackTrace();
        }
        return jsonObject;

    }
}