com.lightbox.android.bitmap.BitmapLoader.java Source code

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Here is the source code for com.lightbox.android.bitmap.BitmapLoader.java

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/**
 * Copyright (c) 2012 Lightbox
 *
 * 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.lightbox.android.bitmap;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URI;

import org.apache.commons.io.IOUtils;
import org.apache.http.HttpResponse;

import android.graphics.Bitmap;
import android.graphics.Bitmap.Config;

import com.lightbox.android.cache.BitmapCache;
import com.lightbox.android.network.HttpHelper;
import com.lightbox.android.network.HttpHelper.HttpMethod;
import com.lightbox.android.utils.debug.DebugLog;

/** 
 * This class allows you to load a bitmap, synchronously or in the background, taking care for you of memory caching,
 * disk caching, and background task.
 * @see BitmapSource
 * @author Fabien Devos & Nilesh Patel
 */
public class BitmapLoader {
    /** Used to tag logs */
    //@SuppressWarnings("unused")
    private static final String TAG = "BitmapLoader";

    private BitmapLoaderTask mBitmapLoaderTask;

    //----------------------------------------------
    // Bitmap Loading API

    public enum Volatility {
        DEFAULT, DO_NOT_CACHE,
    }

    public static Bitmap load(BitmapSource bitmapSource, BitmapSource.Type type, Config config,
            Volatility volatility) throws IOException {
        // Try to get bitmap from memory cache
        Bitmap bitmap = BitmapCache.getInstance().getFromMemory(bitmapSource.getAbsoluteFileName(type));

        // Else load from file on disk, or network
        if (bitmap == null) {
            bitmap = loadFromDiskOrNetwork(bitmapSource, type, config, volatility);
        }

        return bitmap;
    }

    public void loadAsync(BitmapSource bitmapSource, BitmapSource.Type type, Config config, Volatility volatility,
            BitmapLoaderListener listener) {
        // Try to get bitmap from memory cache on main thread
        Bitmap bitmap = BitmapCache.getInstance().getFromMemory(bitmapSource.getAbsoluteFileName(type));

        if (bitmap == null) {
            DebugLog.d(TAG,
                    "Unable to get Bitmap from memory cache, fetching from disk or network. Title: %s - Type: %s - Absolute file name: %s",
                    bitmapSource.getTitle(), type, bitmapSource.getAbsoluteFileName(type));

            mBitmapLoaderTask = new BitmapLoaderTask(bitmapSource, type, config, volatility, listener);
            mBitmapLoaderTask.execute();
        } else {
            listener.onLoaded(bitmap, type, true);
        }
    }

    public void cancel() {
        if (mBitmapLoaderTask != null) {
            mBitmapLoaderTask.cancel();
        }
    }

    //----------------------------------------------
    // Loading

    /*package*/ static Bitmap loadFromDiskOrNetwork(BitmapSource bitmapSource, BitmapSource.Type type,
            Config config, Volatility volatility) throws IOException {
        Bitmap bitmap = null;

        try {
            bitmap = loadFromDiskOrNetworkWithOutOfMemoryRisk(bitmapSource, type, config, volatility);

        } catch (OutOfMemoryError e) {
            DebugLog.d(TAG, "OutOfMemoryError! Trying to reduce the size of the bitmap memory cache.");
            BitmapCache.getInstance().decreaseMemoryCacheSize();
        }

        return bitmap;
    }

    /*package*/ static Bitmap loadFromDiskOrNetworkWithOutOfMemoryRisk(BitmapSource bitmapSource,
            BitmapSource.Type type, Config config, Volatility volatility) throws IOException {
        // Try to load it from disk
        Bitmap bitmap = BitmapCache.getInstance().getFromDisk(bitmapSource.getAbsoluteFileName(type), config)
                .getData();

        // Else try to get it from network
        if (bitmap == null) {
            //Log.e(TAG, "CALLING SERVER file: %s" + bitmapSource.getAbsoluteFileName(type));
            DebugLog.d(TAG,
                    "Unable to get Bitmap from disk cache, fetching from network. Title: %s - Type: %s - Absolute file name: %s",
                    bitmapSource.getTitle(), type, bitmapSource.getAbsoluteFileName(type));

            bitmap = getBitmapFromNetwork(bitmapSource, type, config);
        }

        // Put in memory cache
        if (volatility == Volatility.DEFAULT) {
            BitmapCache.getInstance().putInMemory(bitmapSource.getAbsoluteFileName(type), bitmap);
        }

        return bitmap;
    }

    //----------------------------------------------
    // Bitmap from Network

    private static Bitmap getBitmapFromNetwork(BitmapSource bitmapSource, BitmapSource.Type type, Config config) {
        Bitmap bitmap = null;
        URI uri = bitmapSource.getUri(type);
        if (uri != null) {
            FileOutputStream fos = null;
            try {
                File file = new File(bitmapSource.getAbsoluteFileName(type));

                // Ensure that the directory exist
                file.getParentFile().mkdirs();

                HttpResponse httpResponse = HttpHelper.getInstance().call(HttpMethod.GET, uri, null);

                fos = new FileOutputStream(file);

                IOUtils.copy(httpResponse.getEntity().getContent(), fos);

                bitmap = BitmapCache.getInstance().getFromDisk(bitmapSource.getAbsoluteFileName(type), config)
                        .getData();
            } catch (IOException e) {
                DebugLog.d("", e.getMessage());
                // Return null
            } finally {
                IOUtils.closeQuietly(fos);
            }
        }
        return bitmap;
    }

}