Explain about Constructor with an example.

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What is a Constructor?

A constructor in Java is similar to a method that is invoked when an object of the class is created.

Java Constructor

class Main {
  private String name;

  // constructor
  Main() {
    System.out.println("Constructor Called:");
    name = "Programiz";
  }

  public static void main(String[] args) {

    // constructor is invoked while
    // creating an object of the Main class
    Main obj = new Main();
    System.out.println("The name is " + obj.name);
  }
}

Output:

Constructor Called:
The name is Programiz

In the above example, we have created a constructor named Main(). Inside the constructor, we are initializing the value of the name variable.

Notice the statement of creating an object of the Main class.

Main obj = new Main();

Here, when the object is created, the Main() constructor is called. And, the value of the name variable is initialized.

Hence, the program prints the value of the name variables as Programiz.