This and super uses in java

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The "this" Keyword

The this keyword in Java is a reference variable that refers to the current object of a class.

Why is this keyword used?
This keyword in Java refers to the 'current object' in a method or constructor. It is used to reduce the confusion between class attributes and parameters with the same name

It has several important uses:

Main Uses of this:
1). To refer to current class instance variables (to resolve ambiguity between instance variables and parameters)

public class Student {
    String name;

    public Student(String name) {
        this.name = name; // 'this.name' refers to instance variable
    }
}

Important Notes

a). this cannot be used in a static context (static methods or static blocks)

b). this is automatically added by the compiler in many cases (like when calling instance methods)

c). It helps make code more readable and resolves naming conflicts

d). In event handling or anonymous classes, this can refer to different objects.

The "super" Keyword

The .super keyword in Java is a reference variable that refers to the immediate parent class object. It's used to access parent class members (fields, methods, and constructors) from a subclass.

Main Uses of super
1). Accessing Parent Class Variables
Used when child and parent classes have fields with the same name:

class Parent {
    String color = "white";
}

class Child extends Parent {
    String color = "black";

    void printColor() {
        System.out.println(super.color); // prints "white" (parent)
        System.out.println(color);       // prints "black" (child)
    }
}

2). Calling Parent Class Methods

Used to call overridden methods from the parent class:

class Parent {
    void display() {
        System.out.println("Parent method");
    }
}

class Child extends Parent {
    void display() {
        super.display(); // calls parent's display()
        System.out.println("Child method");
    }
}