Local Chaining in Java

-:Local Chaining in Java:-

Local chaining is the process of calling the another constructor from one constructor present in side the same class.This can be achieved by using this() method.

Example 1:

class Student 

{

int id;

String name;

//this is zero parameterized constructor

Student()

{

System.out.println("Zero parameterized constructor");

}

//this is parameterized constructor

 Student(int id, String name) {

 

this();

System.out.println("parameterized constructor");

this.id = id;

this.name = name;

}

}

public class Demo {

public static void main(String[] args) {

//creating Student class object with parameterized constructor

Student student=new Student(101,"Rama");

}

}

In this example student class have two constructor one is the parameterized constructor and zero parameterized constructor.when I create the object of the Student class with parameterized constructor this() method get execute and takes the control to the zero parameterized constructor.

Example 2:-

class Student 

{

int id;

String name;

String email;

//this is zero parameterized constructor

public Student()

{

System.out.println("Zero parameterized constructor");

}

//this is parameterized constructor

public Student(String name, String email) {

this();

this.name = name;

this.email = email;

System.out.println("parameterized constructor 1");

}

//this is parameterized constructor

public Student(int id, String name, String email) {

this("Raj","Raj@gmail.com");

this.id = id;

this.name = name;

this.email = email;

System.out.println("parameterized constructor 2");

}

@Override

public String toString() {

return "Student [id=" + id + ", name=" + name + ", email=" + email + "]";

}

}

public class Demo {

public static void main(String[] args) {

//creating Student class object with parameterized constructor

Student student=new Student(101,"Ram","Ram@gmail.com");

System.out.println(student);

}

}