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Editorial Team
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Asked: 2026-06-06T21:39:45+00:00

I’m trying to add an edit function to my web app but I’m having

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I’m trying to add an edit function to my web app but I’m having some problems using @RequestParam. The parameter it is getting is null which it shouldn’t be. I’m hoping someone can point out where I have made a mistake.

Here are the methods from the controller :

@RequestMapping(value = "/edit", method = RequestMethod.GET)
public String getEdit(@RequestParam("customerId") Integer customerId, Model model) {
Customer existingCustomer = customerService.retrieveCustomer(customerId);
    model.addAttribute("customerAttribute", existingCustomer);
    return "edit-customer";
}

@RequestMapping(value = "/edit", method = RequestMethod.POST)
public String postEdit(@RequestParam("customerId") Integer customerId,
        @ModelAttribute("customerAttribute") @Valid Customer customer, BindingResult result) {
    if (result.hasErrors()) {
        return "edit-customer";
    }
    customer.setCustomerId(customerId);
    customerService.editCustomer(customer);
    return "redirect:/test/customer/list";

and the two jsp pages

edit-customer.jsp :

<body>

<h1>Edit Existing Customer</h1>

<c:url var="saveUrl" value="/test/customer/edit?customerId=${customerAttribute.customerId}" />
<form:form modelAttribute="customerAttribute" method="POST" action="${saveUrl}">
 <table>
  <tr>
   <td><form:label path="customerId">Customer Id:</form:label></td>
   <td><form:input path="customerId" disabled="true"/></td>
  </tr>

  <tr>
   <td><form:label path="customerCountry">Customer Country</form:label></td>
   <td><form:input path="customerCountry"/></td>
  </tr>

  <tr>
   <td><form:label path="customerName">Customer Name:</form:label></td>
   <td><form:input path="customerName"/></td>
  </tr>

 </table>

 <input type="submit" value="Save" />
</form:form>

</body>

view-all-customers.jsp :

<body>
<a href="<c:url value="/test/home"/>">Home</a>

<h1>Customers</h1>

<c:url var="addUrl" value="/test/customer/add" />
<c:url var="editUrl" value="/test/customer/edit?customerId=${customer.customerId}"/>
<c:if test="${!empty customers}">
<a href="${addUrl}">Add</a> 
</c:if>
<table style="border: 1px solid; width: 500px; text-align:center">
 <thead style="background:#ccc">
  <tr>
   <th>Customer Id</th>
   <th>Customer Country</th>
   <th>Customer Name</th>
   <th colspan="4"></th>
  </tr>
 </thead>
 <tbody>
 <c:forEach items="${customers}" var="customer">
  <tr>
   <td><c:out value="${customer.customerId}" /></td>
   <td><c:out value="${customer.customerCountry}" /></td> 
   <td><c:out value="${customer.customerName}" /></td>
   <td><a href="${editUrl}">Edit</a></td>
  </tr>
 </c:forEach>
 </tbody>
</table>

<c:if test="${empty customers}">
 There are currently no customers in the list. <a href="${addUrl}">Add</a> a customers.
</c:if>

</body>

Can anyone see why Integer customerId in the GET method is null?

Thank you,
D

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1 Answer

  1. Editorial Team

    You’re using ${customer.customerId} before it’s initialized:

    <!-- you use it here -->
<c:url var="editUrl" value="/test/customer/edit?customerId=${customer.customerId}"/>
<c:if test="${!empty customers}">
....
 <tbody>
 <!-- and initialize it here -->
 <c:forEach items="${customers}" var="customer">
  <tr>
   <td><c:out value="${customer.customerId}" /></td>
   <td><c:out value="${customer.customerCountry}" /></td> 
   <td><c:out value="${customer.customerName}" /></td>
   <td><a href="${editUrl}">Edit</a></td>
  </tr>
 </c:forEach>
 </tbody>
</table>

    Simply set editUrl inside the loop:

    <c:if test="${!empty customers}">
....
 <tbody>
 <c:forEach items="${customers}" var="customer">
   <c:url var="editUrl" value="/test/customer/edit?customerId=${customer.customerId}"/>
  <tr>
   <td><c:out value="${customer.customerId}" /></td>
   <td><c:out value="${customer.customerCountry}" /></td> 
   <td><c:out value="${customer.customerName}" /></td>
   <td><a href="${editUrl}">Edit</a></td>
  </tr>
 </c:forEach>
 </tbody>
</table>

    and it should work. You’d have to reset the editUrl for each customer anyway.

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