Spring MVC second Post method @ModelAttribute is null

Question

I have a form that has two buttons, a submit button and an update button.

Here is the JSP:

<%@ page language="java" contentType="text/html; charset=ISO-8859-1" pageEncoding="ISO-8859-1"%>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ taglib prefix="form" uri="http://www.springframework.org/tags/form"%>

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<!-- Bootstrap core CSS !-->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap.min.css">
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/css/bootstrap-theme.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/1.11.3/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.5/js/bootstrap.min.js"></script>

<!--  Custom scripts/styles for this page  !-->
<script type="text/javascript" src="${pageContext.request.contextPath}/static/script/jquery.js"></script>
<script type="text/javascript" src="${pageContext.request.contextPath}/static/script/script.js"></script>
<link rel="stylesheet" type="text/css" href="${pageContext.request.contextPath}/static/css/style.css" /> 

<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Test</title>
</head>
<body>
<!-- General Information Form -->
    <form:form id="form" method="POST" action="${pageContext.request.contextPath}/create" modelAttribute="task">
    <div id="general">
            <table style="width: 224px;">
                <tr>
                    <td colspan="2"><form:select id="systemType" path="systemType" items="${systemTypes}" /></td>
                </tr>
                <tr>
                    <td id="buffer"></td>
                </tr>
                <tr>
                    <td colspan="2"><form:select  id="userName" path="user.fullName" items="${userFullNames}" /></td>
                </tr>
                <tr>
                    <td id="buffer"></td>
                </tr>
                <tr>
                    <td style="width: 50%;"><label for=line><b>Line: </b></label></td>
                    <td><form:select  path="location.line" items="${lines}" id="line"/></td>
                </tr>
                <tr>
                    <td id="buffer"></td>
                </tr>
                <tr>
                    <td style="width: 50%;"><label for=position><b>Position: </b></label></td>
                    <td><form:select path="location.position" items="${positions}" id="position" /></td>
                </tr>
                <tr>
                    <td id="buffer"></td>
                </tr>
                <tr>
                    <td colspan="2">
                    <input id="submitButton" type="submit" name="submit" value=Submit />
                    <input style="display:none;" id="updateButton" type="submit" name="update" value="Update" />
                    <input id="cancel" style="float: right;" type="Reset" value="Cancel"  />
                    </td>
                </tr>
            </table>
        </div>
</form:form>
</body>
</html>

Here is my controller:

@Controller
@RequestMapping("/")
public class HomeController {

private TaskService taskService;

@Autowired
public void setTaskService(TaskService taskService) {
    this.taskService = taskService;
    }

@RequestMapping(value = "/", method = RequestMethod.GET)
public String initForm(Model model, HttpServletRequest request) {
    Task task = new Task();

    model.addAttribute("task", task);
    return "home";
}

@RequestMapping(value="/create", params="submit", method = RequestMethod.POST)
public String submitForm(@ModelAttribute("task")Task task,BindingResult result, Model model) { 

    taskService.create(task);
    return "redirect:/";
}

@RequestMapping(value="/create", params="update", method = RequestMethod.POST)
public String updateForm(@ModelAttribute("task")Task task, BindingResult result, Model model) {

   System.out.println("Updating: " + task.toString());          
   taskService.update(task);

   return "redirect:/";
}

The idea being that hitting the submit button will make a new item, and the update button will edit an existing one. The two .POST methods have different parameters specified to distinguish them.

The submit button is working as expected . However when the update button is pressed a Task object is delivered to the updateForm controller method - but all of its fields are null.

I am not sure why the form is binding the fields to the Task correctly on the submit method, but seemingly creating a new Task and not binding it at all in the update method.

I am inclined to just combine these methods into a single controller method and use some Java logic to determine whether to submit/update based on the parameter - but am curious as to what I'm missing and why this doesn't work.

Answer 1

Ok, I feel very stupid. This was not a SpringMVC issue at all. The problem was caused by a Jquery method that was disabling a part of the form. This gave the appearance that the form was not binding, but actually it was just binding to null values.

Spring MVC second Post method @ModelAttribute is null

Question

1 answers

solution1
0 2015-09-06 04:59:37

Spring MVC second Post method @ModelAttribute is null

Question

1 answers

solution1 0 2015-09-06 04:59:37

solution1
0 2015-09-06 04:59:37