Genson: Convert json to list of objects

Step 1: Instantiate Genson object

Genson genson = new Genson();

Step 2: Use following snippet to conver json to list of objects.

public List<T> getListOfObjects(String json, GenericType<List<T>> list) {

         return genson.deserialize(json, list);

}

public class Employee {
 private String id;
 private String firstName;
 private String lastName;
 private String password;

 public String getId() {
  return id;
 }

 public void setId(String id) {
  this.id = id;
 }

 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 getPassword() {
  return password;
 }

 public void setPassword(String password) {
  this.password = password;
 }

 @Override
 public String toString() {
  StringBuilder builder = new StringBuilder();
  builder.append("Employee [id=").append(id).append(", firstName=")
    .append(firstName).append(", lastName=").append(lastName)
    .append(", password=").append(password).append("]");
  return builder.toString();
 }

}

import java.util.List;

import com.owlike.genson.GenericType;
import com.owlike.genson.Genson;

public class JSONUtil<T> {
 private static Genson genson = new Genson();

 public static String getJson(Object obj) {
  return genson.serialize(obj);
 }

 public T deserializeJson(String json, Class<T> clazz) {
  return genson.deserialize(json, clazz);
 }

 public List<T> getListOfObjects(String json, GenericType<List<T>> list) {
  return genson.deserialize(json, list);
 }
}

import java.util.ArrayList;
import java.util.List;

import com.owlike.genson.GenericType;

public class Test {

 public static void main(String args[]) {
  Employee emp1 = new Employee();
  Employee emp2 = new Employee();
  Employee emp3 = new Employee();

  emp1.setId("E432156");
  emp1.setFirstName("Hari krishna");
  emp1.setLastName("Gurram");
  emp1.setPassword("Password123");

  emp2.setId("32452");
  emp2.setFirstName("Senthi");
  emp2.setLastName("Kumaran");

  List<Employee> emps = new ArrayList<>();
  emps.add(emp1);
  emps.add(emp2);
  emps.add(emp3);

  JSONUtil<Employee> util = new JSONUtil<Employee>();

  String json = JSONUtil.getJson(emps);
  System.out.println("Json is ");
  System.out.println(json);
  

  List<Employee> empsTmp = util.getListOfObjects(json,
    new GenericType<List<Employee>>() {
    });

  System.out.println("\nAfter deserialization");
  System.out.println(empsTmp);
 }
}

Output

Json is 
[{"firstName":"Hari krishna","id":"E432156","lastName":"Gurram","password":"Password123"},{"firstName":"Senthi","id":"32452","lastName":"Kumaran","password":null},{"firstName":null,"id":null,"lastName":null,"password":null}]

After deserialization
[Employee [id=E432156, firstName=Hari krishna, lastName=Gurram, password=Password123], Employee [id=32452, firstName=Senthi, lastName=Kumaran, password=null], Employee [id=null, firstName=null, lastName=null, password=null]]

Previous                                                 Next                                                 Home