How do i pass two objects from thymeleaf form to Spring Controller?

Question

I want to pass two objects from thymeleaf form to a controller. Here is my thymeleaf code :

<!DOCTYPE html>
<html lang='en' xmlns:th="http://www.thymeleaf.org">
<head>
<meta charset="ISO-8859-1"/>
<title>Payment Page</title>
</head>
<body>
<h1>Payment List</h1>

<table>
<tr>
 <th>StuId</th>
 <th>Month</th>
 <th>Amount</th>
 
</tr>
<tr th:each="payment:${student.payments}">
<td th:text="${student.id}">2</td>
<td th:text="${payment.month}">devesh</td>
<td th:text="${payment.amount}">23</td>
</tr>
</table>

<h3>Add a Payment</h3>
 <form action="#" th:action= "@{/payments}" th:object="${payment}" method="POST"> 
      <div th:object="${student}" >
 <label for="name">Month:</label>
   <input type="text" name="month" size="50"></input><br/> 
 <label for="amount">Amount:</label> 
   <input type="text" name="amount" size="50"></input><br/>
<input type = "submit"/></form>

</body>
</html>

in form except the payment object which is actually being submitted here , i want to pass student object or id to my controller as any payment should correspond to a particular student. i Could not find any way till now after searching a lot.

PaymentController method where i want to pass the objects , as i am using submit form , i could not pass variable in th:action

@RequestMapping(method = RequestMethod.POST, value = "/{id}/payments")
    public String doPayment(@ModelAttribute("payment") PaymentRecord paymentRecord, @PathVariable int id) {
        Student st = studentService.getStudentInfo(id);
        
        st.addPayments(paymentRecord);
        System.out.println("entered into do payment");
    

        
        
            studentService.addStudent(st);
      
        
        paymentService.doPayment(paymentRecord);
        return "redirect:{id}/payments";
    }

Please suggest. I am stuck here

yeah ok, i can try this but after that how to obtain this id in my controller , i mean is it from Model argument or i need to explicitly add one more argument in my conroller method signature? Sorry actually this is my first web application in spring boot so i have so many questions:) — devesh, Jul 13 '20 at 05:25

riddle_me_this · Accepted Answer · 2020-07-15T21:13:19.013

1

You can do this different ways.

But first, let's shorten the post method annotation from:

@RequestMapping(method = RequestMethod.POST, value = "/{id}/payments")

to

@PostMapping("/{id}/payments")

I would also change the variable id to studentId to make it more clear for the next person reading your code.

Now, include the variable as a hidden input type within the form tags:

<input type="hidden" name="studentId" th:value="${student.id}">

Then you can either

a) Add a String studentId property to your PaymentRecord class. Then in the post method, you can call paymentRecord.getStudentId();

or

b) Add a request parameter for the studentId to your method mapped with @PostMapping. So your method signature can have @RequestParam(String studentId). In this case, the value of the studentId will be fully exposed to the user.

or

c) Use @RequestBody and map the values to a bean. You can read up on this topic further and look at some background with this question.

edited Jul 15 '20 at 21:13

answered Jul 13 '20 at 19:19

riddle_me_this

8,575
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Thanks :). This explanation is exactly what i was looking for :). i will try to implement this – devesh Jul 15 '20 at 19:10
Sure - upvote or accept as an answer if it works for you. Welcome to SO! – riddle_me_this Jul 15 '20 at 21:11
i accepted this answer, it solved my problem but i faced another problem in next step when i redirecting the controller method to another controller method to populate thymeleaf page , i am getting error "Model has no value for key id", i will be posting this problem – devesh Jul 18 '20 at 04:49

score 0 · Answer 2 · answered Jul 13 '20 at 04:03

0

Instead of :

return "redirect:{id}/payments";

try this:

return "redirect:" + id + "/payments";

or (if need leading / in the redirect) :

return "redirect:/" + id + "/payments";

Of if you want to "GET" with multiple objs then you can something like:

 @RequestMapping(value = { "/deleteuserdocument/{docid}/{userid}" }, method = RequestMethod.GET)

This is from my github repo where I am "GET"ting the documentid for a specific userid. Hope this might help.

answered Jul 13 '20 at 04:03

Ajay Kumar

2,906
3
23
46

But my problem is before that redirect statement , i need to obtain Student id from thymeleaf page to my post controller method or am i not getting your suggestion ? – devesh Jul 13 '20 at 05:29

How do i pass two objects from thymeleaf form to Spring Controller?

2 Answers2