How can you use a switch statement in Java?

2 Examples and use cases

Let's see some examples of how to use a switch statement in Java for different scenarios. Suppose you have a variable called day that represents the day of the week as an integer from 1 to 7. You want to print a message depending on the value of day. You could use a switch statement like this:

switch (day) {
  case 1:
    System.out.println("Today is Monday");
    break;
  case 2:
    System.out.println("Today is Tuesday");
    break;
  case 3:
    System.out.println("Today is Wednesday");
    break;
  case 4:
    System.out.println("Today is Thursday");
    break;
  case 5:
    System.out.println("Today is Friday");
    break;
  case 6:
    System.out.println("Today is Saturday");
    break;
  case 7:
    System.out.println("Today is Sunday");
    break;
  default:
    System.out.println("Invalid day");
    break;
}        

This switch statement is equivalent to using multiple if-else statements, but it is more concise and easier to read. You can also use a switch statement with String values. For example, suppose you have a variable called color that represents the color of a traffic light. You want to print an action depending on the value of color. You could use a switch statement like this:

switch (color) {
  case "red":
    System.out.println("Stop");
    break;
  case "yellow":
    System.out.println("Slow down");
    break;
  case "green":
    System.out.println("Go");
    break;
  default:
    System.out.println("Invalid color");
    break;
}        

Another use case for a switch statement is to implement a simple menu system for a console application. For example, suppose you have a variable called choice that represents the user's input from a list of options. You want to execute a different method depending on the value of choice. You could use a switch statement like this:

switch (choice) {
  case 1:
    showProfile();
    break;
  case 2:
    editProfile();
    break;
  case 3:
    deleteProfile();
    break;
  case 4:
    exit();
    break;
  default:
    System.out.println("Invalid choice");
    break;
}        

3 Advantages and limitations

A switch statement in Java has some advantages and limitations compared to using multiple if-else statements. For instance, it can improve the readability and clarity of your code by reducing the number of lines and indentation levels, as well as its performance by using a hash table or a jump table to find the matching case in constant time. Additionally, it can make your code more maintainable and scalable by grouping related cases together and avoiding code duplication. However, it can only handle a finite number of discrete values, and you cannot use it for ranges, intervals, patterns, or complex conditions. Furthermore, it can introduce bugs and errors if you forget to use the break statement or handle the default case properly. Finally, it can become cumbersome and verbose if you have too many cases or long code blocks for each case.

5 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?