An example of adding two numbers in Java using the `Scanner` class

An example of adding two numbers in Java using the `Scanner` class, along with an analogy for each keyword:

import java.util.Scanner; // Importing Scanner class

public class Addition {

    public static void main(String[] args) {

        // Creating a Scanner object named 'scanner' to read input from the console

        Scanner scanner = new Scanner(System.in);

        

        // Prompting the user to enter the first number

        System.out.print("Enter the first number: ");

        

        // Using the 'nextInt()' method of the Scanner class to read an integer input from the user

        int num1 = scanner.nextInt();

        

        // Prompting the user to enter the second number

        System.out.print("Enter the second number: ");

        

        // Using the 'nextInt()' method again to read the second integer input

        int num2 = scanner.nextInt();

        

        // Closing the Scanner object to prevent resource leak

        scanner.close();

        

        // Adding the two numbers

        int sum = num1 + num2;

        

        // Displaying the result

        System.out.println("The sum of " + num1 + " and " + num2 + " is: " + sum);

    }

}

 

Now, let's break down the code and relate each keyword to an analogy:

1. import: 

   - Analogy: Imagine you're building a house, and you need some specific tools. You "import" those tools (packages) into your construction site.

   - Description: The `import` keyword is used to make classes from other packages available in your code. Here, we're importing the `Scanner` class from the `java.util` package.

2. Scanner:

   - Analogy: Think of a scanner at a grocery store checkout. It reads (scans) the items (input) you put on the conveyor belt.

   - Description: `Scanner` is a class in Java that allows you to read input from various sources, like the console.

3. System.in:

   - Analogy: This is like the entrance to your house. It's where things (input) come into your program.

   - Description: `System.in` represents the standard input stream, which typically corresponds to keyboard input.

4. nextInt():

   - Analogy: Imagine you're reading a book, and you want to move to the next page. You call the librarian and ask for the next page number.

   - Description: The `nextInt()` method of the `Scanner` class reads the next token of input as an integer.

5. close():

   - Analogy: When you finish using a tool, you return it to the toolbox and close the lid to keep everything organized and prevent losing tools.

   - Description: The `close()` method is called to release any resources associated with the `Scanner` object once you're done using it.

6. int:

   - Analogy: In a recipe, you specify the quantity of each ingredient. "int" specifies the type (quantity) of the variable.

   - Description: `int` is a primitive data type in Java used to represent integer numbers.

7. main():

   - Analogy: Think of this as the starting point of a race. When the race begins, all the runners start from this point.

   - Description: `main()` is the entry point of a Java program. Execution starts from this method.

8. System.out.println():

   - Analogy: It's like writing a note and sticking it on a bulletin board for everyone to see.

   - Description: `System.out.println()` is used to print a message to the console.

9. +:

   - Analogy: Just like adding numbers in math class, the `+` operator combines two values together.

   - Description: In Java, the `+` operator is used for addition when applied to numeric operands. It's also used for string concatenation when applied to string operands.

By understanding each keyword and its role in the program, you can grasp how the Java program works and how it interacts with the user.