Sample JSON Array Payload

[
  {
    "firstName": "Amod",
    "lastName": "Mahajan",
    "gender": "Male",
    "age": 28,
    "salary": 10000.56,
    "married": false
  },
  {
    "firstName": "Animesh",
    "lastName": "Prashant",
    "gender": "Male",
    "age": 30,
    "salary": 20000.56,
    "married": true
  },
  {
    "firstName": "Kitty",
    "lastName": "Gupta",
    "gender": "Female",
    "age": 26,
    "salary": 30000.56,
    "married": false
  }
]

Above JSON Array is a collection of JSON Objects or a List of Employees. We have created a Employee POJO class in previous post and we can reuse the same. That is how reusability is one of the major advantage of POJO classes.

Employee POJO

package RestfulBookerPojo;
 
public class Employee {
 
	// private variables or data members of pojo class
	private String firstName;
	private String lastName;
	private String gender;
	private int age;
	private double salary;
	private boolean married;
	
	// Getter and setter methods
	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 String getGender() {
		return gender;
	}
	public void setGender(String gender) {
		this.gender = gender;
	}
	public int getAge() {
		return age;
	}
	public void setAge(int age) {
		this.age = age;
	}
	public double getSalary() {
		return salary;
	}
	public void setSalary(double salary) {
		this.salary = salary;
	}
	public boolean getMarried() {
		return married;
	}
	public void setMarried(boolean married) {
		this.married = married;
	}
}

We do not need any other classes. We just need to create a List of Employees . Below code snippets shows how can we convert a Java Object in to a JSON Array and vice versa.

package RestfulBookerPojo;
 
import java.util.ArrayList;
import java.util.List;
 
import org.testng.annotations.Test;
 
import com.fasterxml.jackson.core.JsonProcessingException;
import com.fasterxml.jackson.core.type.TypeReference;
import com.fasterxml.jackson.databind.ObjectMapper;
 
public class ListOfEmployeesSerializationDeserialization {
 
	public String allEmployeeJson;
 
	@Test
	public void createListOfEmployeesJSONArrayFromEmployeePOJOClass() throws JsonProcessingException {
		// Create first employee
		Employee amod = new Employee();
		amod.setFirstName("Amod");
		amod.setLastName("Mahajan");
		amod.setAge(29);
		amod.setGender("Male");
		amod.setSalary(10000.56);
		amod.setMarried(false);
 
		// Create second employee
		Employee animesh = new Employee();
		animesh.setFirstName("Animesh");
		animesh.setLastName("Prashant");
		animesh.setAge(30);
		animesh.setGender("Male");
		animesh.setSalary(20000.56);
		animesh.setMarried(true);
 
		// Create third employee
		Employee kitty = new Employee();
		kitty.setFirstName("Kitty");
		kitty.setLastName("Gupta");
		kitty.setAge(27);
		kitty.setGender("Female");
		kitty.setSalary(30000.56);
		kitty.setMarried(false);
 
		// Creating a List of Employees
		List<Employee> allEMployees = new ArrayList<Employee>();
		allEMployees.add(amod);
		allEMployees.add(animesh);
		allEMployees.add(kitty);
 
		// Converting a Java class object to a JSON Array payload as string
		ObjectMapper objectMapper = new ObjectMapper();
		allEmployeeJson = objectMapper.writerWithDefaultPrettyPrinter().writeValueAsString(allEMployees);
		System.out.println(allEmployeeJson);
	}
 
	@Test
	public void getPojoFromEmployeeObject() throws JsonProcessingException {
		// Converting EMployee json Array string to Employee class object
		ObjectMapper objectMapper = new ObjectMapper();
		List<Employee> allEmploeesDetails = objectMapper.readValue(allEmployeeJson,
				new TypeReference<List<Employee>>() {
				});
		for (Employee emp : allEmploeesDetails) {
			System.out.println("========================================================");
			System.out.println("First Name of employee : " + emp.getFirstName());
			System.out.println("Last Name of employee : " + emp.getLastName());
			System.out.println("Age of employee : " + emp.getAge());
			System.out.println("Gender of employee : " + emp.getGender());
			System.out.println("Salary of employee : " + emp.getSalary());
			System.out.println("Marital status of employee : " + emp.getMarried());
			System.out.println("========================================================");
		}
	}
}

Output

[ {
  "firstName" : "Amod",
  "lastName" : "Mahajan",
  "gender" : "Male",
  "age" : 29,
  "salary" : 10000.56,
  "married" : false
}, {
  "firstName" : "Animesh",
  "lastName" : "Prashant",
  "gender" : "Male",
  "age" : 30,
  "salary" : 20000.56,
  "married" : true
}, {
  "firstName" : "Kitty",
  "lastName" : "Gupta",
  "gender" : "Female",
  "age" : 27,
  "salary" : 30000.56,
  "married" : false
} ]
========================================================
First Name of employee : Amod
Last Name of employee : Mahajan
Age of employee : 29
Gender of employee : Male
Salary of employee : 10000.56
Marital status of employee : false
========================================================
========================================================
First Name of employee : Animesh
Last Name of employee : Prashant
Age of employee : 30
Gender of employee : Male
Salary of employee : 20000.56
Marital status of employee : true
========================================================
========================================================
First Name of employee : Kitty
Last Name of employee : Gupta
Age of employee : 27
Gender of employee : Female
Salary of employee : 30000.56
Marital status of employee : false
========================================================