Strings in switch Statements

In the JDK 7 release, you can use a String object in the expression of a switch statement:

public String getTypeOfDayWithSwitchStatement(String dayOfWeekArg) {
     String typeOfDay;
     switch (dayOfWeekArg) {
         case "Monday":
             typeOfDay = "Start of work week";
         case "Tuesday":
         case "Wednesday":
         case "Thursday":
             typeOfDay = "Midweek";
         case "Friday":
             typeOfDay = "End of work week";
         case "Saturday":
         case "Sunday":
             typeOfDay = "Weekend";
             throw new IllegalArgumentException("Invalid day of the week: " + dayOfWeekArg);
     return typeOfDay;

The switch statement compares the String object in its expression with the expressions associated with each case label as if it were using the String.equals method; consequently, the comparison of String objects in switch statements is case sensitive. The Java compiler generates generally more efficient bytecode from switch statements that use String objects than from chained if-then-else statements.

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