java - getting child class object in parent abstract class function

I am trying to write an abstract class which will map the string values to the object member-variables and vice versa using ObjectMapper of jackson-databind. This abstract class will be extended by each pojo of json.

import java.io.IOException;    
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;

public abstract class JsonToString {

    public JsonToString toObject(String jsonString){

        ObjectMapper mapper = new ObjectMapper();
        try {
            mapper.readValue(jsonString, this.getClass());//problem
            System.out.println("inside object function of jsontostring : "+this);
        } catch (JsonParseException e) {
            System.out.println("Exception occured in mapping jsonString received to object" + e);
        } catch (JsonMappingException e) {
            System.out.println("Exception occured in mapping jsonString received to object" + e);
        } catch (IOException e) {
            System.out.println("Exception occured in mapping jsonString received to object" + e);
        }
        return this;        
    }
    public String toString(){
        ObjectMapper mapper = new ObjectMapper();
        String json = new String();
        try {
            json = mapper.writeValueAsString(this);
        } catch (JsonProcessingException e) {
            System.out.println("Trouble in mapping object to string in json class : "+this.getClass().getName());
        }
        return json;
    }   
}

this class will be extended by each json pojo.

So here I want to return the object of child class for which the mappings has been done. Can someone please help me get the object and return it.