Execution flow of program by JVM- Part 1

Program 1- Execution Flow of a program involving static block, instance block, parent and child Constructor

/*Static block of parent is executed first because it is

loaded first and static blocks are called when the class is loaded.*/

class Parentt {

     /* parent static block called -1st*/

     static {

          System.out.println("Parent static block");

     }

     /* Parent Instance block called prior to

      * child IB once object is created -2nd */

     {

          System.out.println("Parent initialisation  block");

     }

     /*Parent constructor called prior to child constructor

      * once instance block is called - 3rd */

     public Parentt() {

          System.out.println("Parent Constructor");

     }

}

class Childd extends Parentt {

     /* child static block called after parent static block - 1st */

     static {

          System.out.println("Child static block");

     }

     /* Instance block called once object is created -2nd */

     {

          System.out.println("Child initialisation block");

     }

    

     /*Child constructor called once instance block is called - 3rd*/

     public Childd() {

          System.out.println("Child Constructor");

     }

}

public class ExecutionFlow {

     /* S(static blocks) -I(Instance Blocks) -Constructors */

     public static void main(String[] args) {

          new Childd();

     }

}

Output

Parent static block

Child static block

Parent initialization block

Parent Constructor

Child initialization block

Child Constructor