How to find out if a Object isa integer or isa string or isa boolean?
<p>I have an object and I want to detect what type is, so I can call</p>

<pre><code>if (obj isa Integer)
  put(key,integerval);  
if (obj isa String)
    put(key,stringval);  
if (obj isa Boolean)
    put(key,booleanval);
</code></pre>
