How to serialize the order of properties using Jackson library in Java?

@JsonPropertyOrder is a annotation used at the class level . It takes as an attribute a list of fields that defines the order in which the fields appear in the string generated by JSON serialization of the object. Properties included in the annotation declaration can be serialized first (in the order they are defined), followed by any properties not included in the definition.

Syntax

public @interface JsonPropertyOrder

Example

import com.fasterxml.jackson.core.*;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.annotation.JsonPropertyOrder;
import java.util.*;
import java.io.*;
public class JsonPropertyOrderTest {
   public static void main(String args[]) throws JsonGenerationException, JsonMappingException,        IOException {
      Employee emp = new Employee();
      emp.setFirstName("Adithya");
      emp.setEmpId(25);
      emp.setLastName("Jai");
      emp.getTechnologies().add("Java");
      emp.getTechnologies().add("Scala");
      emp.getTechnologies().add("Python");
      ObjectMapper mapper = new ObjectMapper();
      mapper.writerWithDefaultPrettyPrinter().writeValue(System.out, emp);
   }
}
// Employee class
@JsonPropertyOrder({
   "firstName",
   "lastName",
   "technologies",
   "empId"
})
class Employee {
   private int empId;
   private String firstName;
   private String lastName;
   private List<String> technologies = new ArrayList<>();
   public int getEmpId() {
      return empId;
   }
   public void setEmpId(int empId) {
      this.empId = empId;
   }
   public String getFirstName() {
      return firstName;
   }
   public void setFirstName(String firstName) {
      this.firstName = firstName;
   }
   public String getLastName() {
      return lastName;
   }
   public void setLastName(String lastName) {
      this.lastName = lastName;
   }
   public List<String> getTechnologies() {
      return technologies;
   }
   public void setTechnologies(List<String> technologies) {
      this.technologies = technologies;
   }
}

Output

{
   "firstName" : "Adithya",
   "lastName" : "Jai",
   "technologies" : [ "Java", "Scala", "Python" ],
   "empId" : 125
}

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