<form:form id="A" commandName="objectA">
   <input type="hidden" name="id" value="1101" />
</form:form>

<form:form id="B" commandName="objectB">
   <input type="hidden" name="id" value="1102" />
</form:form>

<form:form id="C" commandName="objectC">
   <input type="hidden" name="id" value="1103" />
</form:form>

<form:form id="D" commandName="objectD">
   <input type="hidden" name="id" value="1104" />
</form:form>

url  : "myController/myRequestMapping",
data : $("#A").serialize()+"&"
      +$("#B").serialize()+"&"
      +$("#C").serialize()+"&"
      +$("#D").serialize(),

@RequestMapping(value="/myRequestMapping")
public void myFunction(AClass a,BClass b,CClass c,DClass d){
  System.out.println("A's ID is:"+a.getId());    //Prints 1101
  System.out.println("B's ID is:"+b.getId());    //Prints 1101 instead of 1102
  System.out.println("C's ID is:"+c.getId());    //Prints 1101 instead of 1103
  System.out.println("D's ID is:"+d.getId());    //Prints 1101 instead of 1104
}

public class Form {

    private Long id;

    public Form(){}

        //getters and setters
}

public class AllForms extends ArrayList<Form> {}

var myarray = [
        {id: $('#A').find('input[name="id"]').val()},
        {id: $('#B').find('input[name="id"]').val()},
        {id: $('#C').find('input[name="id"]').val()},
        {id: $('#D').find('input[name="id"]').val()}
        ];

var jsonStr = JSON.stringify(myarray);

url  : "myController/myRequestMapping",
data : jsonStr

@RequestMapping(value="//myController/myRequestMapping", method=RequestMethod.POST)
public @ResponseBody AllForms process(@RequestBody AllForms allForms){

    System.out.println(allForms);
    return allForms;
}

$.post("myController/myRequestMapping",{jsonStr : jsonStr},function(e) {
        console.log('success: '+e);
    }, "json");

@RequestMapping(value="/myController/myRequestMapping", method=RequestMethod.POST)
public @ResponseBody String process(@RequestParam String jsonStr){
      System.out.println(jsonStr);

      //convert here Form instance from jsonStr

    return jsonStr;
}