this keyword in Java

 

🔷  this Keyword in Java

The this keyword is a reference to the current object — the object whose method or constructor is being called.

✅ Common Uses of this:

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🔸 1. Distinguish instance variables from parameters

class Student {
    String name;

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

    void printName() {
        System.out.println("Name: " + this.name);
    }
}

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🔸 2. Call another constructor (Constructor Chaining)

class Book {
    String title;
    int pages;

    // Constructor with one parameter
    Book(String title) {
        this(title, 0);  // Call another constructor
    }

    // Constructor with two parameters
    Book(String title, int pages) {
        this.title = title;
        this.pages = pages;
    }

    void display() {
        System.out.println(title + " - " + pages + " pages");
    }
}

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🔸 3. Return current object

class Demo {
    Demo getObject() {
        return this;
    }
}