Using superclass methods as instance methods

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An instance method cannot override a static method, and a static method cannot hide an instance method, The following table summarizes what happens when you define a method with the same signature as a method in a superclass

Example_snippet/controller/utility/_using.js/ public class MyClass { pri. . .
public class MyClass {
   private int anInt = 4;
   //Overrides toString in Object class.
   public String toString() {
      return "Instance of MyClass. anInt = " + anInt;
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Classes in Java exist in a hierarchy, A class in Java can be declared as a subclass of another class using the extends keyword

Example_snippet/controller/utility/_using.js/ class IntegerCalculator { . . .
    class IntegerCalculator {
       int sum;

    class DecimalCalculator extends IntegerCalculator {
       double sum;
Step 2 continued with int s = super.sum;. . .
    int s = super.sum;
Step 3 continued with DecimalCalculator dc = new. . .
    DecimalCalculator dc = new DecimalCalculator();
    IntegerCalculator ic = dc;

    int s = ic.sum; // accesses IntegerCalculator sum
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If a subclass defines a static method with the same signature as a static method in the superclass, then the method in the subclass hides the one in the superclass,,An instance method in a subclass with the same signature (name, plus the number and the type of its parameters) and return type as an instance method in the superclass overrides the superclass's method

Example_snippet/controller/utility/_using.js/ public class Animal { publ. . .
public class Animal {
   public static void testClassMethod() {
      System.out.println("The static method in Animal");
   public void testInstanceMethod() {
      System.out.println("The instance method in Animal");
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There are two methods to call the instance variables and methods of the superclass (parent class) in the child class,,2

Example_snippet/controller/utility/_using.js/ Parent class: GFG Child class. . .
Parent class: GFG
Child class: GFGChild
Step 2 continued with This is the helloworld class T. . .
This is the helloworld class
This is the GFG1 class
helloworld is the name
Step 3 continued with GFG class: parent class Arrayl. . .
GFG class: parent class
Arraylist class: Derived class
Step 4 continued with This is the constructor Hello . . .
This is the constructor
Hello world
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This is because variables in Java do not follow polymorphism and overriding is only applicable to methods, not variables, And when an instance variable in a child class has the same name as an instance variable in a parent class, then the instance variable is chosen from the reference type

Example_snippet/controller/utility/_instance.js/ class Parent { // Declarin. . .
class Parent {
   // Declaring instance variable by name `x`
   String x = "Parent`s Instance Variable";

   public void print() {

class Child extends Parent {

   // Hiding Parent class's variable `x` by defining a variable in child class with same name.
   String x = "Child`s Instance Variable";

   public void print() {

      // If we still want to access variable from super class, we do that by using `super.x`
      System.out.print(", " + super.x + "\n");
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An instance method must not override a factory method in a COBOL superclass nor a static method in a Java superclass,,An instance method that is defined in a subclass is said to override an inherited instance method that would otherwise be accessible in the subclass if the two methods have the same signature

Example_snippet/controller/utility/_instance.js/ Linkage section. 01 inDebit . . .
Linkage section.
01 inDebit pic S9(9) binary.
Procedure Division using by value inDebit.

It's actually not inheriting from superclass (list), but creating reference to list,extend method, Meta Stack Overflow ,Thanks for contributing an answer to Stack Overflow!, Stack Overflow Public questions & answers

Example_snippet/controller/utility/_instance.js/ id(list.extend) Out: 310204466. . .
Out: 3102044666032

Out: 3102044666032