Parameter Checking in JSP Page using struts tags

In 2 of my screens I am invoking a pop-up window and the same pop-up window in a 3rd screen

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I am passing the request parameter here

<a href="#" onClick="window.open('searchContactName.do?param=contact','searchContact','resizable=1,width=710,
height=625,status=1,scrollbars=1');" >?</a>

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I am NOT passing the request parameter here

<input type="button" value="LookUp" onClick="window.open('searchContactName.do',
'searchContact','resizable=1,width=710,height=625,
status=1,scrollbars=1');" />

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Here is the pop-up window JSP code

<input type="button" onClick="window.close()" value="cancel" />
<logic:present parameter="param" >
<logic:equal parameter="param" value="contact">
<input type="button" onClick="setContactInformation('abc','contactTable');" value="ok"/>
</logic:equal>
</logic:present>
<logic:notPresent parameter="param" >
<input type="button" onClick="setContactName('abc');" value="ok"/>
</logic:notPresent>