Constructors

A constructor is a special method that initializes an object when it is created. It has the same name as the class and no return type (not even void).

Syntax:

class ClassName {
    ClassName(parameters) {
        // initialization code
    }
}

Example:

class Book {
    String title;
    String author;

    // Constructor
    Book(String t, String a) {
        title = t;
        author = a;
    }
}

Calling a constructor: Using the new keyword.

Book myBook = new Book("1984", "Orwell");

Key points:

• Constructors can be overloaded (different parameter lists).
• If no constructor is defined, Java provides a default no‑argument constructor.
• Constructors cannot be static, final, or abstract.
• They can call other constructors using this().