edu.illinois.whereru.FriendBuilder.java Source code

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Here is the source code for edu.illinois.whereru.FriendBuilder.java

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/*
* 
* Copyright (C) 2012 Hyuk Don Kwon
*
* 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 edu.illinois.whereru;

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.concurrent.ExecutionException;

import org.json.JSONObject;

import android.content.Context;
import android.widget.Toast;

import com.google.android.maps.OverlayItem;

/**
 * Globally shared class to build and keep friends objects. 
 * 
 * TODO: figure out if this is the best way to keep friends objects.
 * @author don
 *
 */
public class FriendBuilder {

    /* Globally shared list of friends */
    private static HashMap<String, Friend> friends = new HashMap<String, Friend>();

    /**
     * Build friends list from DB data.
     * 
     * @param context application context
     */
    public static void build(Context context) {

        try {

            JSONObject json = getFriendInfoFromDB(context); // get data from DB

            List<Profile> profiles = JSONObjectParser // extract profiles
                    .parseDistinctProfile(json);

            List<OverlayItem> locations = JSONObjectParser // extract overlays
                    .parseOverlayItems(json);

            for (Profile profile : profiles) {

                if (friends.containsKey(profile.getId())) { //If this friend already exists
                    // update the profile of with possibly a new one
                    Friend friend = friends.get(profile.getId());
                    friend.setProfile(profile);
                } else {
                    // Create a new friend for with this profile
                    friends.put(profile.getId(), new Friend(context, profile));
                }
            }

            Friend friend = null;
            String prevId = "";

            /* Update locations to corresponding friend object.
             * Assumes the data returned from DB is ordered by friend id.
             */
            for (OverlayItem location : locations) {
                String id = ((MarkerOverlayItem) location).getId();

                if (!prevId.equals(id)) {
                    friend = friends.get(id);
                }

                friend.getOverlay().addOverlay(location);
            }

        } catch (Exception e) {
            e.printStackTrace();
            Toast.makeText(context, "Couldn't load friend information...", Toast.LENGTH_SHORT).show();
        }
    }

    /**
     * Returns profiles of all friends.
     * @return list of profiles
     */
    public static List<Profile> getProfiles() {

        List<Profile> profiles = new ArrayList<Profile>();

        for (Object friend : ((HashMap<String, Friend>) friends).values().toArray())
            profiles.add(((Friend) friend).getProfile());

        return profiles;
    }

    /**
     * Returns overlays of all friends.
     * @return list of overlays
     */
    public static List<FriendOverlay> getOverlays() {

        List<FriendOverlay> overlays = new ArrayList<FriendOverlay>();

        for (Object friend : ((HashMap<String, Friend>) friends).values().toArray())
            overlays.add(((Friend) friend).getOverlay());

        return overlays;
    }

    /**
     * Returns a friend with a specific id
     * @param id friend's id
     * @return friend with the id
     */
    public static Friend getFriend(String id) {
        return friends.get(id);
    }

    /* Retrieves data from DB */
    private static JSONObject getFriendInfoFromDB(Context context) throws InterruptedException, ExecutionException {
        DBConnector connector = new DBConnector();
        String userId = context.getSharedPreferences(MainPageActivity.PREFERENCE_NAME, 0)
                .getString(MainPageActivity.PREF_USER_ID, "-1");
        connector.execute(DBConnector.GET_USER_INFO, userId);

        return connector.get();
    }
}