poisondog.android.image.ImageCache.java Source code

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Here is the source code for poisondog.android.image.ImageCache.java

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/*
 * Copyright (C) 2013 Google Inc.
 * Copyright (C) 2013 Adam Huang
 *
 * 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 poisondog.android.image;

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import android.os.AsyncTask;
import android.support.v4.util.LruCache;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import org.apache.commons.vfs2.FileObject;
import org.apache.commons.vfs2.FileSystemException;

/**
 * @author poisondog <poisondog@gmail.com>
 */
public class ImageCache {
    private LruCache<String, BitmapDrawable> mMemoryCache;
    private ImageDiskCache mImageDiskCache;
    //   private final Object mDiskCacheLock = new Object();
    //   private boolean mDiskCacheStarting = true;
    private static final int DISK_CACHE_SIZE = 1024 * 1024 * 10; // 10MB

    public ImageCache(Context context, FileObject cacheDirectory) {
        final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
        final int cacheSize = maxMemory / 4;

        mMemoryCache = new LruCache<String, BitmapDrawable>(cacheSize) {
            @Override
            protected void entryRemoved(boolean evicted, String key, BitmapDrawable oldValue,
                    BitmapDrawable newValue) {
                if (RecyclingBitmapDrawable.class.isInstance(oldValue)) {
                    ((RecyclingBitmapDrawable) oldValue).setIsCached(false);
                }
            }

            @Override
            protected int sizeOf(String key, BitmapDrawable bitmap) {
                ByteArrayOutputStream bao = new ByteArrayOutputStream();
                bitmap.getBitmap().compress(Bitmap.CompressFormat.PNG, 100, bao);
                return bao.toByteArray().length / 1024;
            }
        };
        new InitDiskCacheTask().execute(cacheDirectory);
    }

    class InitDiskCacheTask extends AsyncTask<FileObject, Void, Void> {
        @Override
        protected Void doInBackground(FileObject... params) {
            //         synchronized (mDiskCacheLock) {
            mImageDiskCache = ImageDiskCache.open(params[0], DISK_CACHE_SIZE);
            //            mDiskCacheStarting = false; // Finished initialization
            //            mDiskCacheLock.notifyAll(); // Wake any waiting threads
            //         }
            return null;
        }
    }

    class PutMemoryCacheTask extends AsyncTask<Pair, Void, Void> {
        @Override
        protected Void doInBackground(Pair... params) {
            mMemoryCache.put(params[0].mKey, params[0].mBitmap);
            return null;
        }
    }

    class Pair {
        public String mKey;
        public BitmapDrawable mBitmap;

        public Pair(String key, BitmapDrawable bitmap) {
            mKey = key;
            mBitmap = bitmap;
        }
    }

    public void addBitmapToCache(String key, BitmapDrawable bitmap) throws FileSystemException, IOException {
        //      if (getBitmapFromMemCache(key) == null) {
        //         if (RecyclingBitmapDrawable.class.isInstance(bitmap)) {
        //            ((RecyclingBitmapDrawable) bitmap).setIsCached(true);
        //         }
        //         new PutMemoryCacheTask().executeOnExecutor(AsyncTask.SERIAL_EXECUTOR, new Pair(key, bitmap));
        //      }
        //      synchronized (mDiskCacheLock) {
        if (mImageDiskCache != null && mImageDiskCache.get(key) == null) {
            mImageDiskCache.put(key, bitmap.getBitmap());
        }
        //      }
    }

    public Bitmap getBitmapFromCache(String key) throws FileSystemException {
        BitmapDrawable bitmap = getBitmapFromMemCache(key);
        if (bitmap != null)
            return bitmap.getBitmap();
        return getBitmapFromDiskCache(key);
    }

    private BitmapDrawable getBitmapFromMemCache(String key) {
        return mMemoryCache.get(key);
    }

    private Bitmap getBitmapFromDiskCache(String key) throws FileSystemException {
        //      synchronized (mDiskCacheLock) {
        //         while (mDiskCacheStarting) {
        //            try {
        //               mDiskCacheLock.wait();
        //            } catch (InterruptedException e) {}
        //         }
        if (mImageDiskCache != null) {
            return mImageDiskCache.get(key);
        }
        //      }
        return null;
    }
}