content: /*******************************************************************************
   * Copyright 2011-2013 Sergey Tarasevich
   *
   * 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.nostra13.universalimageloader.cache.memory.impl;
  
  import android.graphics.Bitmap;
  import com.nostra13.universalimageloader.cache.memory.LimitedMemoryCache;
  
  import java.lang.ref.Reference;
  import java.lang.ref.WeakReference;
  import java.util.Collections;
  import java.util.Iterator;
  import java.util.LinkedHashMap;
  import java.util.Map;
  import java.util.Map.Entry;
  
  /**
   * Limited {@link Bitmap bitmap} cache. Provides {@link Bitmap bitmaps} storing. Size of all stored bitmaps will not to
   * exceed size limit. When cache reaches limit size then the least recently used bitmap is deleted from cache.<br />
   * <br />
   * <b>NOTE:</b> This cache uses strong and weak references for stored Bitmaps. Strong references - for limited count of
   * Bitmaps (depends on cache size), weak references - for all other cached Bitmaps.
   *
   * @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
   * @since 1.3.0
   */
  public class LRULimitedMemoryCache extends LimitedMemoryCache {
  
  	private static final int INITIAL_CAPACITY = 10;
  	private static final float LOAD_FACTOR = 1.1f;
  
  	/** Cache providing Least-Recently-Used logic */
  	private final Map<String, Bitmap> lruCache = Collections.synchronizedMap(new LinkedHashMap<String, Bitmap>(INITIAL_CAPACITY, LOAD_FACTOR, true));
  
  	/** @param maxSize Maximum sum of the sizes of the Bitmaps in this cache */
  	public LRULimitedMemoryCache(int maxSize) {
  		super(maxSize);
  	}
  
  	@Override
  	public boolean put(String key, Bitmap value) {
  		if (super.put(key, value)) {
  			lruCache.put(key, value);
  			return true;
  		} else {
  			return false;
  		}
  	}
  
  	@Override
  	public Bitmap get(String key) {
  		lruCache.get(key); // call "get" for LRU logic
  		return super.get(key);
  	}
  
  	@Override
  	public Bitmap remove(String key) {
  		lruCache.remove(key);
  		return super.remove(key);
  	}
  
  	@Override
  	public void clear() {
  		lruCache.clear();
  		super.clear();
  	}
  
  	@Override
  	protected int getSize(Bitmap value) {
  		return value.getRowBytes() * value.getHeight();
  	}
  
  	@Override
  	protected Bitmap removeNext() {
  		Bitmap mostLongUsedValue = null;
  		synchronized (lruCache) {
  			Iterator<Entry<String, Bitmap>> it = lruCache.entrySet().iterator();
  			if (it.hasNext()) {
  				Entry<String, Bitmap> entry = it.next();
  				mostLongUsedValue = entry.getValue();
  				it.remove();
  			}
  		}
  		return mostLongUsedValue;
  	}
  
  	@Override
  	protected Reference<Bitmap> createReference(Bitmap value) {
  		return new WeakReference<Bitmap>(value);
  	}
  }
  