com.nostra13.universalimageloader.core.assist.MemoryCacheUtil Maven / Gradle / Ivy
/*******************************************************************************
* 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.core.assist;
import android.graphics.Bitmap;
import com.nostra13.universalimageloader.cache.memory.MemoryCacheAware;
import com.nostra13.universalimageloader.core.ImageLoaderConfiguration;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.List;
/**
* Utility for generating of keys for memory cache, key comparing and other work with memory cache
*
* @author Sergey Tarasevich (nostra13[at]gmail[dot]com)
* @since 1.6.3
*/
public final class MemoryCacheUtil {
private static final String URI_AND_SIZE_SEPARATOR = "_";
private static final String WIDTH_AND_HEIGHT_SEPARATOR = "x";
private MemoryCacheUtil() {
}
/**
* Generates key for memory cache for incoming image (URI + size).
* Pattern for cache key - [imageUri]_[width]x[height].
*/
public static String generateKey(String imageUri, ImageSize targetSize) {
return new StringBuilder(imageUri).append(URI_AND_SIZE_SEPARATOR).append(targetSize.getWidth()).append(WIDTH_AND_HEIGHT_SEPARATOR).append(targetSize.getHeight()).toString();
}
public static Comparator createFuzzyKeyComparator() {
return new Comparator() {
@Override
public int compare(String key1, String key2) {
String imageUri1 = key1.substring(0, key1.lastIndexOf(URI_AND_SIZE_SEPARATOR));
String imageUri2 = key2.substring(0, key2.lastIndexOf(URI_AND_SIZE_SEPARATOR));
return imageUri1.compareTo(imageUri2);
}
};
}
/**
* Searches all bitmaps in memory cache which are corresponded to incoming URI.
* Note: Memory cache can contain multiple sizes of the same image if only you didn't set
* {@link ImageLoaderConfiguration.Builder#denyCacheImageMultipleSizesInMemory()
* denyCacheImageMultipleSizesInMemory()} option in {@linkplain ImageLoaderConfiguration configuration}
*/
public static List findCachedBitmapsForImageUri(String imageUri, MemoryCacheAware memoryCache) {
List values = new ArrayList();
for (String key : memoryCache.keys()) {
if (key.startsWith(imageUri)) {
values.add(memoryCache.get(key));
}
}
return values;
}
/**
* Searches all keys in memory cache which are corresponded to incoming URI.
* Note: Memory cache can contain multiple sizes of the same image if only you didn't set
* {@link ImageLoaderConfiguration.Builder#denyCacheImageMultipleSizesInMemory()
* denyCacheImageMultipleSizesInMemory()} option in {@linkplain ImageLoaderConfiguration configuration}
*/
public static List findCacheKeysForImageUri(String imageUri, MemoryCacheAware memoryCache) {
List values = new ArrayList();
for (String key : memoryCache.keys()) {
if (key.startsWith(imageUri)) {
values.add(key);
}
}
return values;
}
/**
* Removes from memory cache all images for incoming URI.
* Note: Memory cache can contain multiple sizes of the same image if only you didn't set
* {@link ImageLoaderConfiguration.Builder#denyCacheImageMultipleSizesInMemory()
* denyCacheImageMultipleSizesInMemory()} option in {@linkplain ImageLoaderConfiguration configuration}
*/
public static void removeFromCache(String imageUri, MemoryCacheAware memoryCache) {
List keysToRemove = new ArrayList();
for (String key : memoryCache.keys()) {
if (key.startsWith(imageUri)) {
keysToRemove.add(key);
}
}
for (String keyToRemove : keysToRemove) {
memoryCache.remove(keyToRemove);
}
}
}