Java Switch with Strings

Introduced in Java 7, you can use switch statement with Strings. This makes code more readable as sometimes the string value of switch case variable makes more sense. Let’s see how can we achieve this:

Java Switch with Strings Examples

Example 1: Checking day of the week using switch case

public class SwitchStringExample {
    public static void main(String[] args) {
        String dayOfWeek = "Tuesday";

        switch (dayOfWeek) {
            case "Monday":
                System.out.println("First day of the week");
                break;
            case "Tuesday":
                System.out.println("Second day of the week");
                break;
            case "Wednesday":
                System.out.println("Third day of the week");
                break;
            case "Thursday":
                System.out.println("Two days to go for weekend");
                break;
            case "Friday":
                System.out.println("A day before weekend");
                break;
            case "Saturday":
            case "Sunday":
                System.out.println("Weekend");
                break;
            default:
                System.out.println("The data is invalid");
                break;
        }
    }
}

Explanation:

1. Variable: The value of the variable dayOfWeek determines which case is to be executed.
2. Switch Statement: The switch statement evaluates the value of dayOfWeek, the value can be an expression.
3. Case Labels: Case label is a string literal in this example. When the value of dayOfWeek matches a case label, the corresponding block of code is executed.
4. Break Statement: After the execution of case block, the break statement terminates the further execution.
5. Default Case: The default case is executed if none of the other cases match.

Points to Note:

• Case Sensitivity: The comparison of variable and case literal is case-sensitive, which means “Tuesday” and “tuesday” would not be considered a match.
• Efficiency: The switch statement with strings internally uses hashCode() and equals()methods of the String class, making it relatively efficient.
• Null Values: If the value of String variable is null, a NullPointerException will be thrown. It is always advisable to ensure that the string is not null before using it in a switch statement.

Example 2: Determining Type of Beverage

public class BeverageTypeExample {
    public static void main(String[] args) {
        String beverage = "Tea";

        switch (beverage) {
            case "Coffee":
            case "Tea":
                System.out.println("Hot Beverage");
                break;
            case "Juice":
            case "Soda":
                System.out.println("Cold Beverage");
                break;
            case "Water":
                System.out.println("Normal Beverage");
                break;
            default:
                System.out.println("Unknown Beverage Type");
                break;
        }
    }
}