src/java.desktop/share/classes/java/awt/Container.java

*** 530,540 ****
              throw new IllegalArgumentException("illegal component position");
          }
          if (comp.parent == this) {
              if (index == component.size()) {
                  throw new IllegalArgumentException("illegal component position " +
!                                                    index + " should be less then " + component.size());
              }
          }
          checkAddToSelf(comp);
          checkNotAWindow(comp);
  
--- 530,540 ----
              throw new IllegalArgumentException("illegal component position");
          }
          if (comp.parent == this) {
              if (index == component.size()) {
                  throw new IllegalArgumentException("illegal component position " +
!                                                    index + " should be less than " + component.size());
              }
          }
          checkAddToSelf(comp);
          checkNotAWindow(comp);