Spring MVC - accessing objects from a list in JSP for a form

Question

I am trying to create a form with multiple objects being passed. I am trying to create a form where you can find 'product' and 'customer' and add them to order. I have 2 model classes Customer and Product. Customer has phoneNo variable, Product has name variable. I found that easiest way to pass multiple objects is to add them to list and pass List to a View. That's what I'm doing, but accessing those model objects is a different story.

Controller class:

 @Controller
    public class OrderController {

    @RequestMapping(value="/create_order", method= RequestMethod.GET)
    public ModelAndView create_order() {
        Map<String, Object> model = new HashMap<String, Object>();
        model.put("customer", new Customer());
        model.put("product", new Product());


        return new ModelAndView("create_order", "command", model);
    }
    }

Page:

<form:form method="POST" action="/Persistence_Web/order_confirmation" commandName="model">
<table>
<!-- I tried few different ways of writing it and all fail -->
    <tr><form:label path="model[0].phoneNo">Customer phone number</form:label></tr>
    <tr><form:input path="model[0].phoneNo"></form:input></tr>
....

Solution 1

To refer the attributes Product.name and Customer.phoneNo in your model, you have to refer the names you give in the model plus the attribute name (that must have a getter in the class!!!)

<tr><form:input path="${customer.phoneNo}"></form:input></tr>
<tr><form:input path="${product.name}"></form:input></tr>

*The attributes in the classes MUST have getters and setters if you want to manipulate them in the view. The naming must be:

private int attributeName
public  int getAttributeName()

BUT: as long as the getter method in the class is like your variable name in the view. You can have a getMyCalculation() method WITHOUT myCalculation attribute in order to calculate totals, averages, formatting dates, or whatever you need to show in the view but not store in the model.

Also, for various Products or Customers use a list:

List<Customer> customers = // fill the list!!!
model.put("customers", customers);

And iterate with a <for:earch>

<c:forEach items="${customers}" var="customer">     
    <c:out value="${customer.phoneNo}"/>
</c:forEach>

Solution 2

As far as I understood your question you can't access model object in this way. Please try using spring placeholders ${command.get('customer').phoneNo}.

Comments

[Edgar.A]

Yup thank you, it worked. On example i did with single object path was defined with single string like path="variable", so that got me confused. And for getter - of course it does, but does it matter if it has default naming like "getVariableName()", or can getter have any name as long as it returns variable needed?

[androberz]

Oh, my bad, I haven't noticed that model object are used in the path attr. I meant that to access model's object you have to use plaseholders, and in this way you should specify something like that: ${command.get("customer")}