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Converting POJO into map

I have a Java class having 10 attributes, I want to convert this into 3 maps(Breaking it into 5,3,2 fields resepectively). I did some research and found that Jackson’s ObjectMapper can be used by doing something like this:

 * Using Jackson Databind.
import java.util.HashMap;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JacksonExample {
    private static final ObjectMapper objectMapper = new ObjectMapper();
    public HashMap<String, Object> convert(Person person) {
        HashMap<String, Object> hashMap = objectMapper.convertValue(person, HashMap.class);
        return hashMap;

This will be creating a single map for all the attributes in my POJO.

What I want is have this POJO converted to 3 different maps(which essentialy are fields of a DynamoDB) I can either define 3 POJOs indivdually and use ObjectMapper on each of them separately, or is there some other way to do it where all fields remain in one POJO only?

I explored mapStruct( couldn’t get much out of it. Thoughts?


You can create methods to get required maps.

public class Test {

    public static void main(String[] args) {
        Person person = new Person("Foo", "Bar", "1", "99999", "[email protected]");


class Person {
    private String firstName;
    private String lastName;
    private String id;
    private String mobileNumber;
    private String email;

    public HashMap<String, Object> getNameMap() {
        HashMap<String, Object> map = new HashMap<>();
        map.put("firstName", this.firstName);
        map.put("lastName", this.lastName);
        return map;

    public HashMap<String, Object> getIdMap() {
        HashMap<String, Object> map = new HashMap<>();
        return map;

    public HashMap<String, Object> getContactMap() {
        HashMap<String, Object> map = new HashMap<>();
        map.put("mobileNumber", this.mobileNumber);
        return map;