Want to test that a parameter value is null in querystring
<p>I am using a servlet to do a range of things.</p>

<p>If a particular parameter "t" does not exist I want to do certain types of processing, if it does I want to do different things.</p>

<p>I am trying to test the parameter t (which I save as a String called editType), using the following condition:</p>

<pre><code>String editType = request.getParameter("t");
if(!editType.isEmpty()||!(editType==null)){
    //processing here
}
</code></pre>

<p>How do I do this test properly, because I am getting the problem of a nullpointerexception, because my code always seems to expect a value for "t" I need to be able to create a condition which doesn't expect t (allows it to be null), and do processing in that.</p>
