com.pansapiens.occyd.JSONdecoder.java Source code

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Here is the source code for com.pansapiens.occyd.JSONdecoder.java

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//    This file is part of the Occyd Android Client 
//    - an Android application for geolocation tagging
//    Copyright (C) 2008, Andrew Perry (ajperry@pansapiens.com)
//
//    This program is free software: you can redistribute it and/or modify
//    it under the terms of the GNU Affero 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 Affero General Public License for more details.
//
//    You should have received a copy of the GNU Affero General Public License
//    along with this program.  If not, see <http://www.gnu.org/licenses/>.

package com.pansapiens.occyd;

import java.util.ArrayList;

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

import android.widget.Toast;

public abstract class JSONdecoder {
    /**
    * Abstract utility class for parsing JSON objects (as strings) and
    * returning Java objects.
    */
    public static ArrayList<Post> json2postArray(String json_txt) throws JSONException {
        /**
         * Takes an appropriate JSON format string, returned as a response
         * by the server to a search query, returns an ArrayList
         *  of Post objects. 
         */
        ArrayList<Post> post_results = new ArrayList();

        if (json_txt != null) {
            // http://code.google.com/android/reference/org/json/JSONObject.html
            JSONTokener jsontok = new JSONTokener(json_txt);
            JSONObject json;
            String geohash = null;
            String[] tags = null;

            // TODO: read these from the JSON too
            //String key = null;
            //String user = null;
            //String desc = null;
            //URL link = null;
            // see: http://java.sun.com/j2se/1.4.2/docs/api/java/util/Date.html
            //Date date = null;
            // parse "2008-12-31 03:22:23.350798" format date with:
            // (could have an issue with to many millisecond places SSSSSS .... may need to truncate)
            // SimpleDateFormat dateformat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS");
            // Date date = dateformat.parse(dateString);

            float lat, lon;

            json = new JSONObject(jsontok);

            // catch any error codes in the returned json
            String result = json.getString("result");
            if (!result.equals("done")) {
                return post_results;
            }

            // unpack the json into Post objects, add them to the result list
            JSONArray posts = json.getJSONArray("posts");
            for (int i = 0; i < posts.length(); i++) {
                JSONObject p = posts.getJSONObject(i);
                geohash = (String) p.get("geohash");
                JSONArray coordinates = p.getJSONArray("coordinates");
                lat = (float) coordinates.getDouble(0);
                lon = (float) coordinates.getDouble(1);

                JSONArray t = p.getJSONArray("tags");
                tags = new String[t.length()];
                for (int j = 0; j < t.length(); j++) {
                    tags[j] = t.getString(j);
                }

                Post post = new Post(lat, lon, geohash, tags);
                post_results.add(post);
            }
        }
        return post_results;
    }
}