Question

In a Struts Action, I want to get a parameter from the URL or from a hidden field, when the parameter in the URL is not set.
To retrieve the parameter from the URL is as follows:

String userId = request.getParameter("userId");

But the problem is now, the HTML is based on forms (legacy code). And I observerd that the parameter userId may be reset to null. Is it an option to set the parameter in a form in a hidden field as well? Would I need to define a parameter in the dynaForm for this? How would I retrieve the parameter from the hidden field?

Answer 1

The parameters in hidden fields are set as any other field, also they can be retrieve the same way.

String userID = request.getParameter("userId");

To check if it is null you just:

if(StringUtils.isNotBlank(userId)) {
    // do stuff
}

http://commons.apache.org/lang/apidocs/org/apache/commons/lang/StringUtils.html#isNotBlank(java.lang.String)

*Edit adding more info
request.getParameter doesn’t distinguish between get nor post variables, so if you have a parameter from the URL you can get it with the same method.