My json format is different than default json format accepted by jqgrid , but still code working . How? - json

Question

Situation : I am modifying a friend's web application project . It uses spring MVC and java ,JQgrid and GSON .
Project has a Student.java model class ,StudentDaoImpl.java DAO class and a buisness class containing listStudentData() service that returns a list of Student objects , and project is using jqGrid jquery plugin to display student data in view.jsp.
View.jsp once loaded makes the following ajax request to retrieve student data :
function initiate() {
$.ajax({
type : 'GET',
dataType : "json",
url : 'listStudentData',
success : function (data)
{
$("#tabel").jqGrid({
data: data,
colNames: ["name" ,"id"],
datatype: "local",
colModel:[{
name : 'studentName',
index : 'studentName',
width : '290px'
}, {
name : 'studentId',
index : 'studentId',
width : '220px'
}]
rowNum:25,
viewrecords: true,
pager: "#div",
scrollOffset: 0,
emptyrecords:"No records",
height: 'auto',
caption: "student data",
grouping: false,
groupingView : {},
});
}
});
}
Controller handling this response :
#RequestMapping(value = "/listStudentData", method = RequestMethod.GET)
public #ResponseBody
String listStudentData() {
final List<Student> list = studentBusiness.listStudentData();
return gson.toJson(list);
}
My json response from this controller is as follows :
[{"studentName":"x" , "StudentId" : "x#gmail.com" },{"studentName":"Y" , "StudentId" : "Y#gmail.com"}]
And code is working fine and giving correct output!
Problem : Now i was going through documentation of jqgrid (http://www.trirand.com/jqgridwiki/doku.php?id=wiki:retrieving_data)
there it is clearly stated that json format expected by jqgrid is as follows :
{
"total": "xxx",
"page": "yyy",
"records": "zzz",
"rows" : [
{"id" :"1", "cell" :["cell11", "cell12", "cell13"]},
{"id" :"2", "cell":["cell21", "cell22", "cell23"]}
]
}
and json format generated by gson library that is sent as response is different than this format then how it is working correctly ? I searched the project for a custom JsonReader but couldn'tfind any . Am i missing something if not then how is this code working ?

Answer 1

See the gson reference for gson.toJson(obj)
public String toJson(Object src)
This method serializes the specified object into its equivalent Json representation. This method should be used when the specified object is not a generic type. This method uses Object.getClass() to get the type for the specified object, but the getClass() loses the generic type information because of the Type Erasure feature of Java. See the official document Gson
Parameters: src - the object for which Json representation is to be
created setting for Gson Returns: Json representation of src.
Check this Demo which uses the same data as your json to create jQgrid.

Answer 2

Your json-response is a json array. Therefore, I guess that the section 'Array Data' of the manual applies. You tell it to accept an array by using datatype: "local" (which is, as stated by the manual, the same as datatype: "clientSide")
With colName you already provide the correct information how to interpret the array.
You could try this by changing the value of datatype and see, whether the array response is still used correctly.