2 Questions on StringBuffer

[Ulf Zibis]

Why there are 2 methods which do not use the super method, where I can't 
see any difference? :

     public synchronized char charAt(int index)
     public synchronized void setCharAt(int index, char ch)

Wouldn't ensureCapacity better coded as follows? :
     public void ensureCapacity(int minimumCapacity) {
         if (minimumCapacity > value.length) synchronized {
             ensureCapacity(minimumCapacity);
         }
     }
This would save the synchronization if there is nothing to do.

-Ulf