src/java.desktop/macosx/classes/com/apple/laf/AquaMenuBarBorder.java

@@ -27,19 +27,21 @@
 
 import java.awt.Color;
 import java.awt.Component;
 import java.awt.Graphics;
 import java.awt.Insets;
+import java.io.Serializable;
 
 import javax.swing.border.Border;
 
 import sun.swing.SwingUtilities2;
 
 /**
  * The class represents the border of a {@code JMenuBar}.
  */
-public class AquaMenuBarBorder implements Border {
+public class AquaMenuBarBorder implements Border, Serializable {
+    private static final long serialVersionUID = 7705272283866425302L;
 
     @Override
     public void paintBorder(final Component c, final Graphics g, final int x,
                             final int y, final int width, final int height) {
         g.setColor(Color.gray);