ResourceManager.java

/**
 * Copyright (C) 2013 Colorado School of Mines
 *
 * This file is part of the Interface Software Development Kit (SDK).
 *
 * The InterfaceSDK 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.
 *
 * The InterfaceSDK 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 the InterfaceSDK.  If not, see <http://www.gnu.org/licenses/>.
 */
/* TODO: considerations to be made
-Because this is currently in the sdk, and it's a singleton, the manager would persist
resources across multiple modules. -> Should it even be here?
*/

package edu.mines.acmX.exhibit.stdlib.graphics;

import org.apache.logging.log4j.*;

import javax.imageio.ImageIO;
import java.awt.*;
import java.awt.image.BufferedImage;
import java.io.File;
import java.io.IOException;
import java.util.HashMap;

/**
 *
 * Simple use of a Hash Map that remembers the images so we won't have to keep reading them from disk and scaling
 *
 * Created with IntelliJ IDEA.
 * User: jzeimen
 * Date: 11/14/12
 * Time: 6:02 PM
 * To change this template use File | Settings | File Templates.
 */
public class ResourceManager {
    private static final Logger logger = LogManager.getLogger(ResourceManager.class);

    private static ResourceManager instance;
    private HashMap<String,Image> imageMap;

    private ResourceManager() {
        imageMap = new HashMap<String, Image>();
    }

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

    /**
     * Put in the file name as the key and it will either go find you the image, or give you its cached one.
     * @param key
     * @return
     */
    public Image getImage(String key) {
        //If we don't have the image go create it and put it here.
        if(!imageMap.containsKey(key)) {
            BufferedImage img;
            try {
                img = ImageIO.read(new File(key));
            } catch (IOException e) {
                throw new RuntimeException("File error: " + key);
            }
            //Calculate the rounded scaled height
            int newHeight = (int) Math.round(img.getHeight());
            int newWidth = (int) Math.round(img.getWidth());

            BufferedImage ret = (BufferedImage)img;
            BufferedImage tmp = new BufferedImage(newWidth, newHeight, BufferedImage.TYPE_INT_ARGB);
            Graphics2D g2 = tmp.createGraphics();
            g2.setRenderingHint(RenderingHints.KEY_INTERPOLATION, RenderingHints.VALUE_INTERPOLATION_BILINEAR);
            g2.drawImage(ret, 0, 0, newWidth, newHeight, null);
            g2.dispose();

            ret=tmp;
            imageMap.put(key, ret);
        }
        return imageMap.get(key);
    }



}