我找到了答案。似乎只有在指定了多个选项时，属性文件中的choice语句才能正常工作。所以你必须指定至少一个else分支
如果我改写我的例子：

I found an answer. It seems that choice statement in properties file works properly only if more than one choice is specified. So you have to specify at least one "else branch" If i rewrite my example:

xxx.yyy.plural={0,choice,2#testy|2<test}