Struts : checkbox status is unchanged if i use back button and uncheck it.

Question

hi
I have a couple of checkboxes in a jsp page used in struts framework. I am using DynaValidatorForm as form bean with session scope, so it means the properties are mapped only in the struts-config.xml. the checkboxes' property names are checkbox1 and checkbox2.
now the in the action class, i do:
public ActionForward execute(ActionMapping mapping,
            ActionForm form,
            HttpServletRequest request,
            HttpServletResponse response)
     throws Exception {
          DynaValidatorForm dynaform = (DynaValidatorForm)form;
                                          System.out.println("1st checkbox value:"+ dynaform.get("checkbox1") );
                                          System.out.println("2nd checkbox value:"+ dynaform.get("checkbox2") );
}Now if I check the first checkbox and press on submit button, the action class prints out:
1st checkbox value: on
2nd checkbox value: off
this is as expected
Now I click on the back button, then i uncheck the first checkbox and click on submit.
the output is same as before, i.e.:
1st checkbox value: on //wrong
2nd checkbox value: off
I expected it to be
1st checkbox value: off
2nd checkbox value: off
That means if in a session if i check on checkbox 'on', and i go back and uncheck it, the uncheck is never stored, i.e. the property is never set to 'off' .
Now if i check the second one, and click on submit, output is :
1st checkbox value: on //expected off
2nd checkbox value: on //correct
now i go back and uncheck the 2nd checkbox (the first checkbox is already unchecked before), click submit and i get this output:
1st checkbox value: on //expected off
2nd checkbox value: on //expected off
Please let me know what is happening. I expect the values of uncheck boxes to be 'off'
thanks
Tanveer

Answer 1

The String[] thing is only useful when you have multiple checkboxes of the same name.
What is the scope of the form bean? Request or session? If it's request, then that makes no sense. If it's session, then it does make sense because the same bean is being used, and as a result, the values are not really reset. And since HTML forms work by not submitting anything for unchecked checkboxes, then the server doesn't get anything in the request form data to know to change the checkbox to any other value.
If you are using session scope, then make sure you have a good reason to. Otherwise, use request.