What is super java
Answer : In java super has two forms:
- First used to calls the superclass constructor
- Second used to access a member of the superclass that has been hidden by a member of a subclass.
Example 1 calling superclass constructor:
Note: subclass can call constructor defined in its superclass with use of the following form of super:
super(arg-list);
arg-list specifies any arguments needed by the constructor in the superclass. super( ) must always be the first statement executed inside a subclass constructor.
package com.javahonk.stringtest; public class Department extends Employee { String departmentName; public Department(String firstName, String lastName, String departmentName) { super(firstName, lastName); this.departmentName = departmentName; } public static void main(String[] args) { Department department= new Department("Java", "Honk", "IT"); System.out.println("First Name: "+department.firstName +" Last Name: "+department.lastName +" Deppartment: "+department.departmentName); } } class Employee { String firstName; String lastName; public Employee(String firstName, String lastName) { super(); this.firstName = firstName; this.lastName = lastName; } }
Output:
Example 2 when super used to access a member of the superclass that has been hidden :
package com.javahonk.stringtest; public class Department extends Employee { // overrides printSubClassMethod in Superclass public void testMethod() { super.testMethod(); System.out.println("I am in subclass."); } public static void main(String[] args) { Department department= new Department(); department.testMethod(); } } class Employee { public void testMethod() { System.out.println("I am in Superclass."); } }
Output:
