* cache loaded icons

source/net/filebot/ResourceManager.java

@@ -4,42 +4,58 @@ import static java.util.Arrays.*;
 
 import java.awt.Image;
 import java.awt.Toolkit;
-import java.io.IOException;
 import java.net.URL;
 import java.util.List;
+import java.util.stream.Collectors;
 
-import javax.imageio.ImageIO;
 import javax.swing.Icon;
 import javax.swing.ImageIcon;
 
+import net.filebot.util.WeakValueHashMap;
+
 public final class ResourceManager {
 
+	private static final WeakValueHashMap<String, Icon> cache = new WeakValueHashMap<String, Icon>(256);
+
 	public static Icon getIcon(String name) {
 		return getIcon(name, null);
 	}
 
 	public static Icon getIcon(String name, String def) {
-		URL resource = getImageResource(name, def);
+		Icon icon = null;
 
+		// try cache
+		synchronized (cache) {
+			icon = cache.get(name);
+			if (icon != null) {
+				return icon;
+			}
+		}
+
+		URL resource = getImageResource(name, def);
 		if (resource == null) {
 			return null;
 		}
 
 		if (Settings.isMacApp()) {
 			// load sun.awt.image.ToolkitImage or sun.awt.image.MultiResolutionToolkitImage (via @2x convention)
-			Image image = Toolkit.getDefaultToolkit().getImage(resource);
-			return new ImageIcon(image);
+			icon = new ImageIcon(Toolkit.getDefaultToolkit().getImage(resource));
 		} else {
-			return new ImageIcon(resource);
+			icon = new ImageIcon(resource);
 		}
+
+		// update cache
+		synchronized (cache) {
+			cache.put(name, icon);
+		}
+
+		return icon;
 	}
 
 	public static List<Image> getApplicationIcons() {
-		Image[] images = new Image[3];
-		images[0] = ResourceManager.getImage("window.icon.small");
-		images[1] = ResourceManager.getImage("window.icon.medium");
-		images[2] = ResourceManager.getImage("window.icon.large");
-		return asList(images);
+		return getApplicationIconURLs().stream().map(it -> {
+			return Toolkit.getDefaultToolkit().getImage(it);
+		}).collect(Collectors.toList());
 	}
 
 	public static List<URL> getApplicationIconURLs() {
@@ -54,14 +70,6 @@ public final class ResourceManager {
 		return getIcon(String.format("flags/%s", languageCode));
 	}
 
-	public static Image getImage(String name) {
-		try {
-			return ImageIO.read(getImageResource(name));
-		} catch (IOException e) {
-			throw new RuntimeException(e);
-		}
-	}
-
 	/**
 	 * Get the URL of an image resource in this jar. Image must be located in <code>resources/</code> and the file type is assumed to be png.
 	 *