src/java.desktop/unix/classes/sun/awt/X11/XTextFieldPeer.java

@@ -279,16 +279,19 @@
         repaintText();
     }
 
     @Override
     public void setFont(Font f) {
+        boolean isChanged = false;
         synchronized (getStateLock()) {
             font = f;
             if (xtext != null && xtext.getFont() != f) {
                 xtext.setFont(font);
+                isChanged = true;
             }
         }
+        if (isChanged)
         xtext.validate();
     }
 
     /**
      * Deselects the highlighted text.