Constructor Overloading

Same class name, different parameter lists — Java picks the right constructor based on your arguments.

The Movie Class

public class Movie { private String title; private String director; private int year; private double rating; }

Constructor 1 — No Arguments (Defaults)

public Movie() {
    this.title = "Unknown";
    this.director = "Unknown";
    this.year = 0;
    this.rating = 0.0;
}

Constructor 2 — Title and Year

public Movie(String title, int year) {
    this.title = title;
    this.year = year;
    this.director = "Unknown";
    this.rating = 0.0;
}

Constructor 3 — All Fields

public Movie(String title, String director, int year, double rating) {
    this.title = title;
    this.director = director;
    this.year = year;
    this.rating = rating;
}

Create a Movie

No arguments needed — all fields will use default values.

Title (String) Year (int)

Title (String) Director (String) Year (int) Rating (double)

Created Object

Field	Value	Source

How Java Picks the Right Constructor

Java matches by the number and types of arguments you pass. Click each row to reveal the match.

new Movie() → 0 args → Constructor 1 0 arguments = no-arg constructor

new Movie("Inception", 2010) → String, int → Constructor 2 String + int matches (String title, int year)

new Movie("The Dark Knight", "Nolan", 2008, 9.0) → String, String, int, double → Constructor 3 4 args with matching types = full constructor

Click a constructor button above to see which constructor Java calls and how the object is built.