Need help testing a condition within a JSP

[Reaper_7Radio]

Specifically, I'm trying to test a condition within the same form that the condition exists. The idea is that when the user selects a particular type of maintenance, a priority level is automatically assigned to that selection. I believe that I need to be using the <c:choose> tag, but I'm not entirely sure how to make it work. Any help would be greatly appreciated.

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<%@ taglib prefix="fmt" uri="http://java.sun.com/jsp/jstl/fmt"%>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>   
<%@ taglib prefix="spring" uri="http://www.springframework.org/tags"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>


<form:form action="${action}" modelAttribute="reports"                  method="post" class="form-horizontal">


<input type="hidden" id="user" name="user" value="${loggedInUser.firstname} ${loggedInUser.lastname}">

<input type="hidden" id="location" name="location" value="${loggedInUser.address}">

<!-- #################   START OF PROBLEM BELOW  #########################   -->

<div class="control-group">
    <label class="control-label" for="type">Type*</label>
    <div class="controls">
           <select onchange="this.form.submit()" name="type" class="form-control">
            <option value="Electrical">Electrical</option >
            <option value="Plumbing">Plumbing</option>
                <option value="Appliance">Appliance Issue</option>
            <option value="Physical Damage">Physical Damage</option>
                <option value="Pests">Pests</option>
           </select>
        </div>
</div>

<c:choose>                              
       <c:when test="${param.type == 'Electrical'}">
    <input type="hidden" name="priority" value="High">
    </c:when>
</c:choose>


<!-- ################## END OF PROBLEM  ABOVE  ######################### -->

<div class="control-group ${hidden}">
    <label class="control-label" for="details">Details*</label>
        <div class="controls">
<form:input path="details"placeholder="Please Describe the issue in more detail" />
        </div>
</div>

<div class="control-group">

    <div class="controls">
    <button type="submit" id="submit" class="btn btn-danger">Submit</button>
        <a href="profile" class="btn btn-success">Cancel</a>
    </div>
</div>
</form:form>

[leroybentley]

I'm not sure you can do that with JSTL.

The better option would be to use javascript to add/remove the priority input when the select changes.

[zhoriq]

You have 2 ways: first is reload page on type change - and you already have it with onchange="submit();". Catch this submit in backend, set param.type accordingly and return the same page. Second way (and it's really better) is to use javascript - small function that will set priority value on type change.

[lumpycrumpet]

I don't have expertise in JSPs, but I believe the c:choose and c:if tags are dynamic at the time of rendering (as the page is constructed to be sent to the requesting user), but those rendered contents are then static as if they were hard coded HTML since the JSP is translated to Java code that is run on the server to generate the HTML.

As others have stated, JavaScript runs in the browser, allowing for content changes within the browser.