de.kp.ames.web.function.dms.cache.ImageCacheManager.java Source code

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Here is the source code for de.kp.ames.web.function.dms.cache.ImageCacheManager.java

Source

package de.kp.ames.web.function.dms.cache;
/**
 * This Java module is part of the
 *  Application Developer Framework
 *
 *  Project: AMES-Web-Service
 *  Package: de.kp.ames.web.function.dms.cache
 *  Module: ImageCacheManager
 *  @author krusche@dr-kruscheundpartner.de
 *
 * Add your semantic annotations within the SemanticAssist tags and
 * mark them with a leading hashtag #:
 *
 * <SemanticAssist>
 *     #cache #dms #function #image #manager #web
 * </SemanticAssist>
 *
 */

/**
 *   Copyright 2012 Dr. Krusche & Partner PartG
 *
 *   AMES-Web-Service is free software: you can redistribute it and/or 
 *   modify it under the terms of the GNU General Public License 
 *   as published by the Free Software Foundation, either version 3 of 
 *   the License, or (at your option) any later version.
 *
 *   AMES- Web-Service is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. 
 * 
 *  See the GNU General Public License for more details. 
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this software. If not, see <http://www.gnu.org/licenses/>.
 *
 */

import java.io.ByteArrayInputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.util.List;

import javax.imageio.ImageIO;

import org.json.JSONArray;
import org.json.JSONObject;

import de.kp.ames.web.core.cache.CacheEntry;
import de.kp.ames.web.core.cache.CacheManager;
import de.kp.ames.web.shared.constants.JsonConstants;

public class ImageCacheManager implements CacheManager {

    private static ImageCacheManager instance = new ImageCacheManager();

    private ImageCache cache = null;

    public static ImageCacheManager getInstance() {
        if (instance == null)
            instance = new ImageCacheManager();
        return instance;
    }

    private ImageCacheManager() {
        this.cache = new ImageCache();
    }

    /* (non-Javadoc)
     * @see de.kp.ames.web.core.cache.CacheManager#setToCache(java.lang.String, java.lang.String, java.lang.String, java.io.InputStream)
     */
    public void setToCache(String key, String name, String mimetype, InputStream stream) throws IOException {
        DmsImage image = new DmsImage(key, name, mimetype, ImageIO.read(stream));
        cache.put(key, image);
    }

    /* (non-Javadoc)
     * @see de.kp.ames.web.core.cache.CacheManager#setToCache(java.lang.String, java.lang.String, java.lang.String, byte[])
     */
    public void setToCache(String key, String name, String mimetype, byte[] bytes) throws IOException {
        DmsImage image = new DmsImage(key, name, mimetype, ImageIO.read(new ByteArrayInputStream(bytes)));
        cache.put(key, image);
    }

    /* (non-Javadoc)
     * @see de.kp.ames.web.core.cache.CacheManager#getFromCache(java.lang.String)
     */
    public CacheEntry getFromCache(String key) {
        if (cache.hasKey(key) == false)
            return null;
        return cache.get(key);
    }

    /* (non-Javadoc)
     * @see de.kp.ames.web.core.cache.CacheManager#removeFromCache(java.lang.String)
     */
    public void removeFromCache(String key) {

        if (cache.hasKey(key) == false)
            return;

        /* 
         * Remove temp file assigned with image
         */
        String path = cache.get(key).getPath();
        if (path != null)
            new File(path).delete();

        cache.remove(key);

    }

    /* (non-Javadoc)
     * @see de.kp.ames.web.core.cache.CacheManager#getJEntries()
     */
    public JSONArray getJEntries() throws Exception {

        JSONArray jEntries = new JSONArray();

        List<CacheEntry> images = cache.getAll();
        for (int ix = 0; ix < images.size(); ix++) {

            DmsImage image = (DmsImage) images.get(ix);
            String key = image.getKey();

            JSONObject jImage = new JSONObject();

            jImage.put(JsonConstants.J_KEY, key);
            jImage.put(JsonConstants.J_NAME, image.getName());

            jImage.put(JsonConstants.J_DESC, "No description available.");
            jImage.put(JsonConstants.J_MIME, image.getMimetype());

            jEntries.put(jEntries.length(), jImage);

        }

        return jEntries;

    }

}