Here's an example of a traditional switch construct that is modifying a variable based on an enum value passed to a method:

enum SingleUsePlastic {STRAW, BAG, SPOON, FORK, KNIFE, PLATE, BOTTLE}; 
 
class Planet { 
    private static long damage; 
    public void use(SingleUsePlastic plastic) { 
        switch(plastic) { 
            case STRAW :    damage += 10; 
                            break; 
            case BAG   :    damage += 11; 
                            break; 
            case SPOON :    damage += 7; 
                            break; 
            case FORK  :    damage += 7; 
                            break; 
            case KNIFE :    damage += 7; 
                            break; 
            case PLATE :    damage += 15; 
                            break; 
            case BOTTLE:    damage = 20; 
                            break; 
        } 
    } 
} 

Let's see how the preceding code changes if we use switch expressions:

damage += switch(plastic) { 
                case STRAW -> 10; 
                case BAG -> 11; 
                case SPOON, FORK, KNIFE -> 7; 
                case PLATE -> 15; 
                case BOTTLE -> 20; 
          }; 

Let's compare the new switch expressions with traditional switch statements. The code in the preceding block, which uses switch expressions, is a lot more concise. You define what to execute on the right of the arrow (->). Also, you no longer need break statements in each switch branch. There's less boilerplate and less likelihood of accidental errors from missing break statements.

The following diagram highlights the changes:

A switch expression offers multiple benefits and features:

• Unlike a switch statement, a switch expression can return a value
• The return value for a switch branch is defined to the right of ->
• The same switch branch can define multiple labels that are separated using ,
• There isn't any default fall through of the control across switch branches
• The code is less verbose

Let's work with the finer details of switch expressions.