Regarding methods were not overridden in StringBuffer and StringBuilder?
<p><code>hashCode()</code> and <code>equals()</code> methods were not overridden in <code>StringBuffer</code> and <code>StringBuilder</code> , I was trying this piece of code below..</p>

<pre><code>    //StringBuffer does not override equals &amp; hashCode
        //StringBuffer s = new StringBuffer("saral");
        //StringBuffer s1 = new StringBuffer("saral");

        StringBuilder s = new StringBuilder("saral");
        StringBuilder s1 = new StringBuilder("saral");          

        //String s = new String("saral");
        //String s1 = new String("saral");

       HashSet set=new HashSet();
        set.add(s);
        set.add(s1);
        set.add(null);
       System.out.println("There are "+set.size()+" elements in the set.");
</code></pre>

<p>The resulting out come I ma getting is 3 in both the case when I use <code>StringBuffer</code> or <code>StringBuilder</code> but 2 in case of string , since string has override the <code>hashCode()</code> and <code>equals()</code> method, please advise.</p>
