Ensure derived icons with the same size share their underlying image resource.

property-loader/src/main/java/com/github/weisj/darklaf/icons/DarkSVGIcon.java

@@ -101,12 +101,12 @@ public class DarkSVGIcon implements DerivableIcon<DarkSVGIcon>, RotateIcon, Seri
         loaded = new AtomicBoolean(false);
     }
 
-    protected DarkSVGIcon(final int width, final int height, final DarkSVGIcon icon) {
+    protected DarkSVGIcon(final int width, final int height, final DarkSVGIcon parent) {
         this.size = new Dimension(width, height);
-        this.icon = icon.icon;
-        this.uri = icon.uri;
-        this.uriSupplier = icon.uriSupplier;
-        this.loaded = icon.loaded;
+        this.icon = parent.icon;
+        this.uri = parent.uri;
+        this.uriSupplier = parent.uriSupplier;
+        this.loaded = parent.loaded;
     }
 
     @Override
@@ -174,15 +174,14 @@ public class DarkSVGIcon implements DerivableIcon<DarkSVGIcon>, RotateIcon, Seri
                  * If we get to here the issue was that the icon hasn't been patched because it isn't loaded as a themed
                  * svg icon.
                  */
-                LOGGER.severe("Icon '" + getName() + "' that defines custom colors isn't loaded as themed icon.");
+                LOGGER.severe("Icon '" + getName(uri) + "' that defines custom colors isn't loaded as themed icon.");
                 return img;
             }
             throw e;
         }
     }
 
-    protected String getName() {
-        ensureURILoaded();
+    protected String getName(final URI uri) {
         String name = uri.toASCIIString();
         name = name.substring(Math.min(name.length() - 1, name.lastIndexOf('/') + 1));
         return name;

property-loader/src/main/java/com/github/weisj/darklaf/icons/DerivableImageIcon.java

@@ -32,17 +32,18 @@ import java.util.function.Supplier;
 import javax.accessibility.*;
 import javax.swing.*;
 
+import com.github.weisj.darklaf.util.LazyValue;
+
 public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Accessible {
 
-    private static final int DEFAULT_SCALING_MODE = Image.SCALE_SMOOTH;
+    private static final int DEFAULT_SCALING_MODE = Image.SCALE_DEFAULT;
     private final int scalingMode;
 
     private int width;
     private int height;
 
-    private Supplier<Image> imageSupplier;
-    private Image original;
-    private Image img;
+    private final LazyValue<Image> original;
+    private final LazyImageValue image;
     private String description;
     private AccessibleContext accessibleContext;
 
@@ -125,7 +126,8 @@ public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Ac
         this.width = width;
         this.height = height;
         this.scalingMode = scalingMode;
-        this.imageSupplier = imageSupplier;
+        this.original = new LazyValue<>(imageSupplier);
+        this.image = new LazyImageValue(this);
     }
 
     /**
@@ -220,10 +222,8 @@ public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Ac
         this.width = width;
         this.height = height;
         this.scalingMode = scalingMode;
-        this.original = img;
-        if (img != null && img.getWidth(null) == width && img.getHeight(null) == height) {
-            this.img = img;
-        }
+        this.original = new LazyValue<>(img);
+        this.image = new LazyImageValue(this);
     }
 
     protected DerivableImageIcon(final DerivableImageIcon parent, final int width, final int height) {
@@ -232,16 +232,7 @@ public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Ac
         this.scalingMode = parent.scalingMode;
         this.original = parent.original;
         this.description = parent.description;
-        this.imageSupplier = parent.imageSupplier;
-        if (this.original != null
-            && this.original.getWidth(null) == width
-            && this.original.getHeight(null) == height) {
-            this.img = this.original;
-        } else if (parent.img != null
-                   && parent.img.getWidth(null) == width
-                   && parent.img.getHeight(null) == height) {
-            this.img = parent.img;
-        }
+        this.image = parent.image.derive(this);
     }
 
     @Override
@@ -249,31 +240,9 @@ public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Ac
         return new DerivableImageIcon(this, width, height);
     }
 
-    protected void ensureOriginalLoaded() {
-        if (original == null && imageSupplier != null) {
-            original = imageSupplier.get();
-            imageSupplier = null;
-        }
-    }
-
-    protected void ensureLoaded() {
-        ensureOriginalLoaded();
-        if (original != null && (width < 0 || height < 0)) {
-            if (width < 0) width = original.getWidth(null);
-            if (height < 0) height = original.getHeight(null);
-        }
-        if (img == null && original != null && width > 0 && height > 0) {
-            if (original.getWidth(null) != width || original.getHeight(null) != height) {
-                img = original.getScaledInstance(width, height, scalingMode);
-            } else {
-                img = original;
-            }
-        }
-    }
-
     @Override
     public void paintIcon(final Component c, final Graphics g, final int x, final int y) {
-        ensureLoaded();
+        Image img = image.get();
         if (img != null) {
             g.drawImage(img, x, y, width, height, null);
         }
@@ -285,19 +254,32 @@ public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Ac
      * @return the image.
      */
     public Image getImage() {
-        ensureLoaded();
+        return image.get();
+    }
+
+    protected Image getOriginal() {
+        Image img = original.get();
+        calculateSize();
         return img;
     }
 
+    private void calculateSize() {
+        Image originalImage = original.get();
+        if (originalImage != null && (width < 0 || height < 0)) {
+            if (width < 0) width = originalImage.getWidth(null);
+            if (height < 0) height = originalImage.getHeight(null);
+        }
+    }
+
     @Override
     public int getIconWidth() {
-        if (width < 0) ensureLoaded();
+        if (width < 0) calculateSize();
         return width;
     }
 
     @Override
     public int getIconHeight() {
-        if (height < 0) ensureLoaded();
+        if (height < 0) calculateSize();
         return height;
     }
 
@@ -392,4 +374,38 @@ public class DerivableImageIcon implements DerivableIcon<DerivableImageIcon>, Ac
             return icon.getIconHeight();
         }
     }
+
+    protected static class LazyImageValue extends LazyValue<Image> {
+
+        private final DerivableImageIcon icon;
+
+        public LazyImageValue(final DerivableImageIcon icon) {
+            super((Image) null);
+            this.icon = icon;
+        }
+
+        public LazyImageValue derive(final DerivableImageIcon icon) {
+            if (this.icon.width == icon.width && this.icon.height == icon.height) {
+                // Make sure all icons with the same dimension share one image.
+                return this;
+            }
+            return new LazyImageValue(icon);
+        }
+
+        @Override
+        protected Image load() {
+            Image originalImage = icon.getOriginal();
+            int width = icon.getIconWidth();
+            int height = icon.getIconHeight();
+            if (originalImage != null && width > 0 && height > 0) {
+                if (originalImage.getWidth(null) != width
+                    || originalImage.getHeight(null) != height) {
+                    return originalImage.getScaledInstance(width, height, icon.scalingMode);
+                } else {
+                    return originalImage;
+                }
+            }
+            return null;
+        }
+    }
 }

property-loader/src/main/java/com/github/weisj/darklaf/icons/IconLoader.java

@@ -263,8 +263,6 @@ public final class IconLoader {
         }
 
         // Icon not found or caching is disabled.
-
-        key.w = w; // Restore key.
         if (isSVGIcon(path)) {
             Icon icon = loadSVGIcon(path, w, h, themed);
             cache(iconMap, key, icon);
@@ -278,15 +276,16 @@ public final class IconLoader {
 
     private Icon getWildcardIcon(final Map<IconKey, Icon> iconMap,
                                  final IconKey iconKey, final int w, final int h) {
-        iconKey.w = -1;
+        iconKey.isWildcardEnabled = true;
         Icon icon = iconMap.get(iconKey);
         if (icon instanceof DerivableIcon) {
             @SuppressWarnings("unchecked")
             Icon derived = ((DerivableIcon<Icon>) icon).derive(w, h);
-            iconKey.w = w;
+            iconKey.isWildcardEnabled = false;
             cache(iconMap, iconKey, derived);
             return derived;
         }
+        iconKey.isWildcardEnabled = false;
         return null;
     }
 
@@ -374,7 +373,7 @@ public final class IconLoader {
      * @return             the ImageIcon.
      */
     ImageIcon createImageIcon(final String path, final String description) {
-        java.net.URL imgURL = getResource(path);
+        URL imgURL = getResource(path);
         if (imgURL != null) {
             return new ImageIcon(imgURL, description);
         } else {
@@ -422,6 +421,7 @@ public final class IconLoader {
         final String path;
         int w;
         int h;
+        boolean isWildcardEnabled;
 
         private IconKey(final String path, final int w, final int h) {
             this.path = path;
@@ -441,7 +441,7 @@ public final class IconLoader {
 
             IconKey iconKey = (IconKey) o;
 
-            if (iconKey.w == -1 || iconKey.h == -1 || this.h == -1 || this.w == -1) {
+            if (iconKey.isWildcardEnabled || this.isWildcardEnabled) {
                 // Math any size.
                 return Objects.equals(path, iconKey.path);
             }

property-loader/src/test/java/com/github/weisj/darklaf/icons/DerivableImageIconTest.java

@@ -0,0 +1,54 @@
+/*
+ * MIT License
+ *
+ * Copyright (c) 2020 Jannis Weis
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ */
+package com.github.weisj.darklaf.icons;
+
+import java.awt.*;
+import java.util.HashSet;
+import java.util.Set;
+
+import org.junit.jupiter.api.Assertions;
+import org.junit.jupiter.api.Test;
+
+public class DerivableImageIconTest {
+
+    @Test
+    public void testCache() {
+        IconLoader loader = IconLoader.get(DerivableImageIconTest.class);
+        DerivableImageIcon icon = (DerivableImageIcon) loader.getIcon("image_icon.png");
+        Set<Image> imageSet = new HashSet<>();
+        for (int i = 0; i < 100; i++) {
+            Image img = ((DerivableImageIcon) loader.getIcon("image_icon.png", 100, 100)).getImage();
+            imageSet.add(img);
+        }
+        Assertions.assertEquals(1, imageSet.size());
+
+        imageSet.clear();
+        icon = icon.derive(50, 50);
+        for (int i = 0; i < 100; i++) {
+            imageSet.add(icon.derive(50, 50).getImage());
+        }
+        Assertions.assertEquals(1, imageSet.size());
+    }
+}

utils/src/main/java/com/github/weisj/darklaf/util/LazyValue.java

@@ -31,8 +31,11 @@ public class LazyValue<T> {
     private Supplier<T> supplier;
     private T value;
 
-    public LazyValue(final Supplier<T> supplier) {
+    public LazyValue(final T value) {
+        this.value = value;
+    }
 
+    public LazyValue(final Supplier<T> supplier) {
         this.supplier = supplier;
     }
 
@@ -40,11 +43,17 @@ public class LazyValue<T> {
         return supplier == null;
     }
 
-    public T get() {
-        if (value == null && supplier != null) {
-            value = supplier.get();
+    protected T load() {
+        if (supplier != null) {
+            T obj = supplier.get();
             supplier = null;
+            return obj;
         }
         return value;
     }
+
+    public T get() {
+        if (value == null) value = load();
+        return value;
+    }
 }