Does the "switch" statement in Java only work with integers?

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Switch Statement With Strings in Java?

Does the "switch" statement in Java only work with integers ?

Can't I write something like this instead ?

switch(string) case "hello": ...

thanks

Not until Java 7 See: http://blogs.sun.com/darcy/entry/project_coin_developer_preview here: http://cr.openjdk.java.net/~darcy/ProjectCoin/ProjectCoin-Documentation-v0.83.html#string_switch — OscarRyz, Mar 04 '11 at 20:12
I am going to say this in capital letters. WHY THE HELL IS THIS QUESTION CLOSED? The other question was asked in **2008**, and we are now in **2011**. That's like 50 years in computer years, and Java has been through some major uncertainties. — irreputable, Mar 04 '11 at 22:03

biziclop · Accepted Answer · 2017-04-14T17:24:09.617

7

This answer is only valid for Java 6 or earlier! Switching on strings has been added in Java 7

14.11 The switch Statement

The type of the Expression must be char, byte, short, int, Character, Byte, Short, Integer, or an enum type (§8.9), or a compile-time error occurs.

Usually, when you need to switch on a string value, you can often work around this limitation by using char (as the string is only ever going to be one character long) or an enum. In your case, enum looks more likely.

edited Apr 14 '17 at 17:24

answered Mar 04 '11 at 20:07

biziclop

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switch does work with String in Java SE 7 – samitgaur Mar 04 '11 at 20:12
@Samit G Not a very good idea if you ask me but still, it's only Java SE 7. – biziclop Mar 04 '11 at 20:13

score 2 · Answer 2 · answered Mar 04 '11 at 20:09

Yes. Until java 6, not with Strings. Tough you can do a workaround with ENUMS, something like:

public enum Day {
    SUNDAY, MONDAY, TUESDAY, WEDNESDAY, 
    THURSDAY, FRIDAY, SATURDAY 
}

switch (day) {
        case MONDAY: System.out.println("Mondays are bad.");
                     break;

        case FRIDAY: System.out.println("Fridays are better.");
                     break;

        case SATURDAY:
        case SUNDAY: System.out.println("Weekends are best.");
                     break;

        default:     System.out.println("Midweek days are so-so.");
                     break;
    }

more easy to read for us humans, right?

source is http://download.oracle.com/javase/tutorial/java/javaOO/enum.html

score 1 · Answer 3 · answered Mar 04 '11 at 20:10

Actually, according to Oracle in Java SE 7 you can use strings with the switch statement

http://download.oracle.com/javase/tutorial/java/nutsandbolts/switch.html

public class StringSwitchDemo {

public static int getMonthNumber(String month) {

    int monthNumber = 0;

    if (month == null) { return monthNumber; }

    switch (month.toLowerCase()) {
        case "january":    monthNumber =  1; break;
        case "february":   monthNumber =  2; break;
        case "march":      monthNumber =  3; break;
        case "april":      monthNumber =  4; break;
        case "may":        monthNumber =  5; break;
        case "june":       monthNumber =  6; break;
        case "july":       monthNumber =  7; break;
        case "august":     monthNumber =  8; break;
        case "september":  monthNumber =  9; break;
        case "october":    monthNumber = 10; break;
        case "november":   monthNumber = 11; break;
        case "december":   monthNumber = 12; break;
        default:           monthNumber =  0; break;
    }

    return monthNumber;
}

public static void main(String[] args) {

    String month = "August";

    int returnedMonthNumber =
      StringSwitchDemo.getMonthNumber(month);

    if (returnedMonthNumber == 0) {
      System.out.println("Invalid month");
    } else {
      System.out.println(returnedMonthNumber);
    }
}

}

score 0 · Answer 4 · answered Mar 04 '11 at 20:07

The switch statement cannot work with strings. Under the bug listing....

"Don't hold your breath"

http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=1223179

although after looking at the upcoming docs posted in another answer, I suppose this feature is available in JDK7.

score 0 · Answer 5 · answered Mar 04 '11 at 20:07

0

Java's tutorial says it works with primitive types (byte, short, char, int) as well as strings. See http://download.oracle.com/javase/tutorial/java/nutsandbolts/switch.html

answered Mar 04 '11 at 20:07

Tom Hamming

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this documentation applies to JDK7 – Brandon Frohbieter Mar 04 '11 at 20:10
This was going to be introduced as a new feature in Java 7. The tutorial carries a warning that it is being updated and might not property reflect Java 6 features anymore. In Java 6, String in switch statements was not yet available. I thought it was cancelled for 7 as well, but apparently not so. Rejoice! – G_H Mar 04 '11 at 20:11

score 0 · Answer 6 · answered Mar 04 '11 at 20:10

0

with java 7 you can use switch with strings. look here

answered Mar 04 '11 at 20:10

sdorra

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Does the "switch" statement in Java only work with integers?

6 Answers6