Switch Statement and Strings

This question already has an answer here:

Why can't I switch on a String? 14 answers

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As far as I know, this is okay:

public static void sortData(short days[], String name[]) {
    char choice;
    Scanner kd = new Scanner(System.in);

    System.out.println("a. Sort by Namenb. Sort by Day");
    choice = kd.next().toCharArray()[0];

    switch (choice) {
    case 'a':
        // do something
        break;
    case 'b';
        // do something else
        break;
    }
}

Not tested

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You could define a list of strings for your accepted choices and use indexOf to find the entered input. After that you can use the index in your switch .

Like this

List<String> options = Arrays.asList("name", "day", "color", "smell");
switch (options.indexOf(choice)) {
case 0: // name
    ...
case 1: // day
    ...
... // etc
default: // none of them
}

However, using the numbers is not very readable.

Another idea: define an enum and use valueOf(choice) . In this case you have to catch an IllegalArgumentException for non matching inputs.

enum Options {
    name, day, color, smell
}

and then

try {
    switch (Options.valueOf(choice)) {
    case name: ...
    case day: ...
    // etc
    }
} catch (IllegalArgumentException ex) {
    // none of them
}

or, finally, you switch to Java 7 ;-)

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