Arrow icons customization

AutoComplete/src/main/java/org/fife/ui/autocomplete/AutoCompleteDescWindow.java

@@ -511,7 +511,47 @@ public void updateUI() {
 		TipUtil.tweakTipEditorPane(descArea);
 		scrollPane.setBackground(descArea.getBackground());
 		scrollPane.getViewport().setBackground(descArea.getBackground());
-		((JPanel)getContentPane()).setBorder(TipUtil.getToolTipBorder());
+		((JPanel) getContentPane()).setBorder(TipUtil.getToolTipBorder());
+
+		ComponentOrientation orientation = ac.getTextComponentOrientation();
+		setArrowIcon(forwardAction, orientation.isLeftToRight(), "forward");
+		setArrowIcon(backAction, orientation.isLeftToRight(), "back");
+	}
+
+	/**
+	 * Sets the appropriate arrow icon for the specified navigation action based on
+	 * the component orientation (Left-to-Right or Right-to-Left) and action type.
+	 * <p>
+	 * This method first checks the {@link UIManager} for a custom icon registered under
+	 * the semantic key. If absent, it loads the default icon resource from the classpath,
+	 * caches it in the {@link UIManager} for future use, and assigns it to the action.
+	 *
+	 * @param action the menu or toolbar action to update with the icon
+	 * @param ltr    {@code true} if the component orientation is Left-to-Right; {@code false} for Right-to-Left
+	 * @param type   the type of navigation action, either {@code "back"} or {@code "forward"}
+	 */
+	private static void setArrowIcon(Action action, boolean ltr, String type) {
+		// Determine the UIManager key based on action type and text direction
+		String key = "back".equals(type) ?
+			(ltr ? "autocomplete.descWindow.backIcon" : "autocomplete.descWindow.forwardIcon") :
+			(ltr ? "autocomplete.descWindow.forwardIcon" : "autocomplete.descWindow.backIcon");
+
+		Icon icon = UIManager.getIcon(key);
+
+		if (icon == null) {
+			// Fallback to default classpath resources if not defined in UIManager
+			String resourceName = key.endsWith("backIcon") ? "arrow_left.png" : "arrow_right.png";
+			URL url = AutoCompleteDescWindow.class.getResource(resourceName);
+
+			if (url != null) {
+				icon = new ImageIcon(url);
+				UIManager.put(key, icon);
+			} else {
+				throw new IllegalArgumentException("Icon resource not found on classpath: " + resourceName);
+			}
+		}
+
+		action.putValue(Action.SMALL_ICON, icon);
 	}
 
 
@@ -578,29 +618,23 @@ void setCompletion(Completion c, String anchor,
 	class ToolBarBackAction extends AbstractAction {
 
 		ToolBarBackAction(boolean ltr) {
-			String img = "org/fife/ui/autocomplete/arrow_" +
-						(ltr ? "left.png" : "right.png");
-			ClassLoader cl = getClass().getClassLoader();
-			Icon icon = new ImageIcon(cl.getResource(img));
-			putValue(Action.SMALL_ICON, icon);
+			setArrowIcon(this, ltr, "back");
 		}
 
 		@Override
 		public void actionPerformed(ActionEvent e) {
-			if (historyPos>0) {
+			if (historyPos > 0) {
 				HistoryEntry pair = history.get(--historyPos);
 				descArea.setText(pair.summary);
-				if (pair.anchor!=null) {
+				if (pair.anchor != null) {
 					//System.out.println("Scrolling to: " + pair.anchor);
 					descArea.scrollToReference(pair.anchor);
-				}
-				else {
+				} else {
 					descArea.setCaretPosition(0);
 				}
 				setActionStates();
 			}
 		}
-
 	}
 
 
@@ -610,23 +644,18 @@ public void actionPerformed(ActionEvent e) {
 	class ToolBarForwardAction extends AbstractAction {
 
 		ToolBarForwardAction(boolean ltr) {
-			String img = "org/fife/ui/autocomplete/arrow_" +
-							(ltr ? "right.png" : "left.png");
-			ClassLoader cl = getClass().getClassLoader();
-			Icon icon = new ImageIcon(cl.getResource(img));
-			putValue(Action.SMALL_ICON, icon);
+			setArrowIcon(this, ltr, "forward");
 		}
 
 		@Override
 		public void actionPerformed(ActionEvent e) {
-			if (history!=null && historyPos<history.size()-1) {
+			if (history != null && historyPos < history.size() - 1) {
 				HistoryEntry pair = history.get(++historyPos);
 				descArea.setText(pair.summary);
-				if (pair.anchor!=null) {
+				if (pair.anchor != null) {
 					//System.out.println("Scrolling to: " + pair.anchor);
 					descArea.scrollToReference(pair.anchor);
-				}
-				else {
+				} else {
 					descArea.setCaretPosition(0);
 				}
 				setActionStates();