gr.scify.newsum.controllers.CacheController.java Source code

Introduction

Here is the source code for gr.scify.newsum.controllers.CacheController.java

Source

/*******************************************************************************
 *
 * Copyright 2013 SciFY NPO <info@scify.org>.
 *
 * This product is part of the NewSum Free Software.
 * For more information about NewSum visit
 *
 *    http://www.scify.gr/site/en/our-projects/completed-projects/newsum-menu-en
 *
 * 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.
 *
 * If this code or its output is used, extended, re-engineered, integrated, 
 * or embedded to any extent in another software or hardware, there MUST be 
 * an explicit attribution to this work in the resulting source code, 
 * the packaging (where such packaging exists), or user interface 
 * (where such an interface exists). 
 * The attribution must be of the form "Powered by NewSum, SciFY" 
 * 
 * @contributor NaSOS (nasos.loukas@gmail.com)
 *******************************************************************************/
package gr.scify.newsum.controllers;

import java.util.Timer;
import java.util.TimerTask;

import android.graphics.Bitmap;
import android.support.v4.util.LruCache;

public class CacheController {

    private static Timer cacheTimer = new Timer();
    public static final long EXPIRATION = 15 * 60 * 1000L; // 15 minutes

    private static LruCache<String, Object> cache = createCache();

    private static LruCache<String, Object> createCache() {
        // set cache clearance
        cacheTimer.purge();
        cacheTimer.scheduleAtFixedRate(new TimerTask() {
            @Override
            public void run() {
                clearCache();
            }
        }, EXPIRATION, EXPIRATION);
        // create cache
        return new LruCache<String, Object>((int) (Runtime.getRuntime().maxMemory() / 3));
    }

    /*
     * Add an object to the cache
     */
    public static <V> void putToCache(String key, V v) {
        if (key == null || v == null)
            return;
        synchronized (cache) {
            if (cache == null)
                cache = createCache();
            // if bitmap mark
            cache.put(key, v);
        }
    }

    /*
     * retrieve object from cache
     */
    @SuppressWarnings("unchecked")
    public static <V> V getFromCache(String key) {
        synchronized (cache) {
            if (cache == null)
                cache = createCache();
            Object data = cache.get(key);
            return (V) data;
        }
    }

    /*
     * remove object from cache
     */
    public static <V> void removeFromCache(String key) {
        synchronized (cache) {
            if (cache == null)
                cache = createCache();
            cache.remove(key);
        }
    }

    /*
     * clear cache
     */
    public static void clearCache() {
        synchronized (cache) {
            if (cache == null)
                return;
            for (String key : cache.snapshot().keySet())
                cache.remove(key);
        }
    }

    /*
     * clear images
     */
    protected static void clearImageCache() {
        synchronized (cache) {
            if (cache == null)
                return;
            for (String key : cache.snapshot().keySet())
                if (cache.get(key) instanceof Bitmap)
                    cache.remove(key);
        }
    }

}