Question:

Consider the following code snippet:

public class Calculator {
  
  public static void main(String[] args) {
    int result = multiply(2, 3);
    System.out.println(result);
  }
  
  public static int multiply(int num1, int num2) {
    return num1 * num2;
  }
  
}

Explain the method declaration and invocation used in the given code.

Answer:

The given code snippet demonstrates the usage of method declaration and invocation. Let's break down the code and discuss each aspect in detail:

First, we have a class declaration named Calculator using the public access modifier. This class contains the main method which is the entry point of execution for Java programs.

Inside the main method, we declare an integer variable result and assign it the value returned by invoking the multiply method with arguments 2 and 3. The multiply method is invoked using the class name Calculator followed by the dot operator . and the method name multiply.

Moving on, the multiply method is declared using the public static access modifiers. The public access modifier allows this method to be accessible from any class, and the static modifier allows the method to be called without creating an instance of the Calculator class.

The method declaration specifies the return type as int since it returns an integer value. It also defines two parameters, num1 and num2, of type int. These parameters act as placeholders for the actual values that will be passed when the method is invoked.

Within the method body, the multiplication of num1 and num2 is performed using the * operator, and the result is returned using the return keyword.

Finally, the computed result is printed to the console using the System.out.println() statement.

In summary, the given code snippet demonstrates the declaration of a method named multiply in the Calculator class, and its subsequent invocation in the main method. The declared method receives two integer arguments, performs the multiplication operation, and returns the result. The returned value is then assigned to the result variable and printed to the console.