<p> The code synchronizes on a boxed primitive constant, such as an Boolean.
<pre>
private static Boolean inited = Boolean.FALSE;
...
  synchronized(inited) { 
    if (!inited) {
       init();
       inited = Boolean.TRUE;
       }
     }
...
</pre>
</p>
<p>Since there normally exist only two Boolean objects, this code could be synchronizing on the same object as other, unrelated code, leading to unresponsiveness
and possible deadlock</p>