com.lillicoder.newsblurry.feeds.DownloadFeedsTask.java Source code

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Here is the source code for com.lillicoder.newsblurry.feeds.DownloadFeedsTask.java

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/**
 * Copyright 2012 Scott Weeden-Moody
 *
 * 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 com.lillicoder.newsblurry.feeds;

import java.io.IOException;
import java.util.Collections;
import java.util.List;
import java.util.Map;

import org.apache.http.HttpResponse;
import org.apache.http.client.methods.HttpGet;
import org.json.JSONException;
import org.json.JSONObject;

import android.content.Context;
import android.util.Log;

import com.lillicoder.newsblurry.R;
import com.lillicoder.newsblurry.exception.ApiRequestException;
import com.lillicoder.newsblurry.net.BaseTask;
import com.lillicoder.newsblurry.net.OnTaskCompletedListener;

/**
 * Task that downloads the current user's feed subscriptions.
 * @author lillicoder
 */
public class DownloadFeedsTask extends BaseTask<Void, Void, List<IFeed>> {

    private static final String TAG = DownloadFeedsTask.class.getSimpleName();

    protected DownloadFeedsTask(Context context, OnTaskCompletedListener<List<IFeed>> listener) {
        super(context, listener);
    }

    @Override
    protected List<IFeed> doInBackground(Void... params) {
        try {
            Context context = this.getContext();

            String feedsUrl = context.getString(R.string.api_feedsUrl);
            HttpGet feedsGet = new HttpGet(feedsUrl);

            // Pull entity and parse JSON response.
            HttpResponse httpResponse = this.executeWebRequest(feedsGet);
            JSONObject responseJson = this.getJsonFromResponse(httpResponse);

            // Save the newly fetched feeds in cache and persistent storage.
            FeedParser parser = new FeedParser(context);
            Map<Integer, Feed> feedsById = parser.parseFeedsById(responseJson);

            FeedCache cache = new FeedCache();
            cache.updateFeeds(feedsById);

            FeedRepository repository = new FeedRepository(this.getContext());
            repository.saveFeeds(feedsById);

            // Sort feeds before returning.
            List<IFeed> feeds = parser.parseFeeds(responseJson);
            Collections.sort(feeds);

            return feeds;
        } catch (ApiRequestException e) {
            Log.e(TAG, EXCEPTION_API_REQUEST_FAILED, e);
            this.setException(e);
        } catch (IOException e) {
            Log.e(TAG, EXCEPTION_FAILED_TO_PARSE_RESPONSE, e);
            this.setException(e);
        } catch (JSONException e) {
            Log.e(TAG, EXCEPTION_UNABLE_TO_CREATE_JSON_FROM_RESPONSE, e);
            this.setException(e);
        }

        return null;
    }

}