Using superclass methods as instance methods

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usinginstancesuperclassmethods
90%

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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88%

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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72%

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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65%

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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75%

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() {
      System.out.println(x);
   }
}

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";

   @Override
   public void print() {
      System.out.print(x);

      // 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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40%

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.
22%

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. . .
id(list.extend)
Out: 3102044666032

id(ListWithLoadMethod.load)
Out: 3102044666032