Java中的“switch” 语句只与整数一起工作吗？

Does the “switch” statement in Java only work with integers?

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Possible Duplicate:
Switch Statement With Strings in Java?

Java中的"Twitter"语句只与整数一起工作吗？

我不能改写这样的东西吗？

开关(串)案例"你好"：…

谢谢

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对。直到Java 6，而不是使用字符串。很难用Enums来解决问题，比如：

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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;
}

对我们人类来说更容易阅读，对吧？

源代码是http://download.oracle.com/javase/tutorial/java/javaoo/enum.html

实际上，根据JavaSE 7中的Oracle，可以使用带有转换语句的字符串。

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

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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);
}
}

}

使用Java 7，可以使用带有字符串的开关。看这里

Java的教程称它与原始类型(字节、短、char、int)以及字符串一起工作。请参阅http://download.oracle.com/javase/tutorial/java/nutsandbolts/switch.html