DEV Community

Edwin Torres
Edwin Torres

Posted on

Using a Switch for Days of the Week

#java #beginners #tutorial #programming

The switch statement is a useful selection statement when there are many values that require different logic.

Here is a program that asks the user to enter a day number (1-7) and outputs the full name of that day of the week.

First, import the Scanner class (for user input), declare the class name, and declare the main method:

import java.util.Scanner; public class Days { public static void main(String[] args) {
Enter fullscreen mode Exit fullscreen mode

Next, declare a Scanner variable and create the object. This object will retrieve user input later:

 Scanner in = new Scanner(System.in);
Enter fullscreen mode Exit fullscreen mode

Declare a variable to store the user input:

 int dayNum;
Enter fullscreen mode Exit fullscreen mode

Ask the user to enter a number:

 System.out.print("Enter a day number (1-7): ");
Enter fullscreen mode Exit fullscreen mode

Use the Scanner object to retrieve the user input. Note that the program will wait here until the user types a value and presses Enter:

 dayNum = in.nextInt();
Enter fullscreen mode Exit fullscreen mode

Create a switch statement that switches on the dayNum variable:

 switch(dayNum) {
Enter fullscreen mode Exit fullscreen mode

Inside the switch statement, add cases for each day. For example, the value 1 will output Monday:

 case 1: System.out.println("Monday"); break;
Enter fullscreen mode Exit fullscreen mode

Here are the other cases. Note that case 5 also outputs TGIF:

 case 2: System.out.println("Tuesday"); break; case 3: System.out.println("Wednesday"); break; case 4: System.out.println("Thursday"); break; case 5: System.out.println("Friday"); System.out.println("TGIF!"); break; case 6: System.out.println("Saturday"); break; case 7: System.out.println("Sunday"); break;
Enter fullscreen mode Exit fullscreen mode

The last case is a default case. This case occurs when the dayNum value has a number outside the range 1-7:

 default: System.out.println("Invalid day number."); break;
Enter fullscreen mode Exit fullscreen mode

Finally, add the closing curly brackets for the switch statement, main method, and class:

 } } }
Enter fullscreen mode Exit fullscreen mode

Here is the complete program:

import java.util.Scanner; public class Days { public static void main(String[] args) { Scanner in = new Scanner(System.in); int dayNum; System.out.print("Enter a day number (1-7): "); dayNum = in.nextInt(); switch(dayNum) { case 1: System.out.println("Monday"); break; case 2: System.out.println("Tuesday"); break; case 3: System.out.println("Wednesday"); break; case 4: System.out.println("Thursday"); break; case 5: System.out.println("Friday"); System.out.println("TGIF!"); break; case 6: System.out.println("Saturday"); break; case 7: System.out.println("Sunday"); break; default: System.out.println("Invalid day number."); break; } } }
Enter fullscreen mode Exit fullscreen mode

Thanks for reading. 😃

Follow me on Twitter @realEdwinTorres for more programming tips and help.

Top comments (0)