receiving json and deserializing as List of object at spring mvc controller

This is not possible the way you are trying it. The Jackson unmarshalling works on the compiled java code after type erasure. So your

public @ResponseBody ModelMap setTest(@RequestBody List<TestS> refunds, ModelMap map) 

is really only

public @ResponseBody ModelMap setTest(@RequestBody List refunds, ModelMap map) 

(no generics in the list arg).

The default type Jackson creates when unmarshalling a List is a LinkedHashMap.

As mentioned by @Saint you can circumvent this by creating your own type for the list like so:

class TestSList extends ArrayList<TestS> { }

and then modifying your controller signature to

public @ResponseBody ModelMap setTest(@RequestBody TestSList refunds, ModelMap map) {

@RequestMapping(
         value="person", 
         method=RequestMethod.POST,
         consumes="application/json",
         produces="application/json")
@ResponseBody
public List<String> savePerson(@RequestBody Person[] personArray) {
    List<String> response = new ArrayList<String>();
    for (Person person: personArray) {
        personService.save(person);
        response.add("Saved person: " + person.toString());
    }
    return response;
}

We can use Array as shown above.

Here is the code that works for me. The key is that you need a wrapper class.

public class Person {

    private String name;
    private Integer age;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getAge() {
        return age;
    }

    public void setAge(Integer age) {
        this.age = age;
    }

    @Override
    public String toString() {
        return "Person [name=" + name + ", age=" + age + "]";
    }

A PersonWrapper class

public class PersonWrapper {

    private List<Person> persons;

    /**
     * @return the persons
     */
    public List<Person> getPersons() {
        return persons;
    }

    /**
     * @param persons the persons to set
     */
    public void setPersons(List<Person> persons) {
        this.persons = persons;
    }
}

My Controller methods

@RequestMapping(value="person", method=RequestMethod.POST,consumes="application/json",produces="application/json")
    @ResponseBody
    public List<String> savePerson(@RequestBody PersonWrapper wrapper) {
        List<String> response = new ArrayList<String>();
        for (Person person: wrapper.getPersons()){
        personService.save(person);
         response.add("Saved person: " + person.toString());
    }
        return response;
    }

The request sent is json in POST

{"persons":[{"name":"shail1","age":"2"},{"name":"shail2","age":"3"}]}

And the response is

["Saved person: Person [name=shail1, age=2]","Saved person: Person [name=shail2, age=3]"]

Solution works very well,

public List<String> savePerson(@RequestBody Person[] personArray)  

For this signature you can pass Person array from postman like

[
{
  "empId": "10001",
  "tier": "Single",
  "someting": 6,
  "anything": 0,
  "frequency": "Quaterly"
}, {
  "empId": "10001",
  "tier": "Single",
  "someting": 6,
  "anything": 0,
  "frequency": "Quaterly"
}
]

Don't forget to add consumes tag:

@RequestMapping(value = "/getEmployeeList", method = RequestMethod.POST, consumes="application/json", produces = "application/json")
public List<Employee> getEmployeeDataList(@RequestBody Employee[] employeearray) { ... }