Ajax with Spring MVC

[Kashif Mughal]

Hi

I am trying with my little knowledge to update the Customer Details onChange event of list, let me tell you the way i am doing it.

I am using simpleFormController that loads the list values, When i select any of the customers from the list i call javascript function that does AJAX process, in this process I am passing URL that invoke the same contoller again. Infact, This is the point where i am confused as i need to see the customer details on same page, But they are not coming on the page but definately coming from DB.

I am wondering if i am doing it right?

code is as follow;

  <script language="Javascript">
var xmlHttp
 
function showAddress(custId)
{alert("CustID : " + custId);
xmlHttp=GetXmlHttpObject();
if (xmlHttp==null)
  {
  alert ("Your browser does not support AJAX!");
  return;
  } 
var url="createOrder.htm";
url=url+"?custId=" + custId;
url=url+"&sid="+Math.random();
xmlHttp.onreadystatechange=stateChanged;
xmlHttp.open("GET",url,true);
xmlHttp.send(null);
}
 
function stateChanged() 
{ 
if (xmlHttp.readyState==4)
{ 
document.getElementById("txtHint").innerHTML=xmlHttp.responseText;
}
}
 
function GetXmlHttpObject()
{
var xmlHttp=null;
try
  {
  // Firefox, Opera 8.0+, Safari
  xmlHttp=new XMLHttpRequest();
  }
catch (e)
  {
  // Internet Explorer
  try
    {
    xmlHttp=new ActiveXObject("Msxml2.XMLHTTP");
    }
  catch (e)
    {
    xmlHttp=new ActiveXObject("Microsoft.XMLHTTP");
    }
  }
return xmlHttp;
}
</script>  
 
.........
 
<spring:bind path="orderImpl.customer">
<tr>
<tr>
<td>
<div align="right" class="contentTblTxt">Select Customer
for Order</div>
</td>
<td><select name='<c :-o	 ut value="${status.expression}"/>'
onchange="showAddress(this.value)">
<option value=""></option>
<c:forEach items="${customers}" var="customer">
<option value='<c :-o	 ut value="${customer.businessTitle}"/>'
<c:if test="${customer.businessTitle == status.value}"> SELECTED</c:if>>
<c :-o	 ut value="${customer.businessTitle}" /></option>
</c:forEach>
</select></td>
</tr>
</spring:bind>

<tr>
<td>
<div align="right" class="contentTblTxt">Name : </div>
</td>
<td class="contentHeaderTxt"><c :-o	 ut value="${cust.fName}"/></td>
</tr>

      public CreateOrderFormController() {
setCommandClass(OrderImpl.class);
setCommandName("orderImpl");
    }
 
    protected Object formBackingObject(HttpServletRequest request) throws Exception {
OrderImpl order = new OrderImpl();
CategoryImpl cat = new CategoryImpl();
ItemImpl item = new ItemImpl();
CustomerImpl cust = new CustomerImpl();
LineItem lineItem = new LineItem();
Set<LineItem> lineItemSet = new HashSet<LineItem>();
 
lineItem.setCategory(cat);
lineItem.setItem(item);
lineItemSet.add(lineItem);
 
order.setCustomer(cust);
order.setLineItemSet(lineItemSet);
return order;
    }  
 
    protected Map referenceData(HttpServletRequest request) throws Exception {
Map model = new HashMap();
 
if (request.getParameter("custId") != null) {
    log.info("Customer ID " + request.getParameter("custId"));
    Customer cust = new CustomerImpl();
    cust.setBusinessTitle(request.getParameter("custId"));
    cust = customerService.findCustomerById(cust);
    log.info("Address " + cust.getfName());
    log.info("Address " + cust.getAccount().getAccountNo());
    // log.info("Address " + cust.getAddress().getStreet());
    model.put("cust", cust);
}
 
List categories = inventoryService.findAllCategories();
System.out.println("listSize" + categories.size());
List customers = customerService.findAllCustomers();
model.put("categories", categories);
model.put("customers", customers);
return model;
    }
 
    // Creating Category into DB
    public void onBindAndValidate(HttpServletRequest request, Object command, BindException errors) throws Exception {
 
OrderImpl ord = (OrderImpl) command;
 
if (errors.hasErrors())
    return;
 
ord = saleService.addOrder(ord);
    }
 
    /** returns ModelAndView(getSuccessView()) */
    public ModelAndView onSubmit(HttpServletRequest request, HttpServletResponse response, Object command,
    BindException errors) throws Exception {
 
ModelAndView mav = new ModelAndView("mainMenu", getCommandName(), command);
return mav;
    }  

[Mark Spritzler]

I don't know Ajax, but I do know that Spring has Spring Javascript which makes doing Ajax calls easy in Spring MVC. Maybe it might be best to use it, rather than trying to re-invent the wheel.

Mark