java - jodatime-PeriodFormatter : suffix only for day/days

Question

我只需要显示天/天的后缀，我该如何实现？它不起作用:

java.lang.IllegalStateException: No field to apply suffix to..

    private PeriodFormatter getDayTextFormatter() {
        return new PeriodFormatterBuilder()
                .printZeroNever()
                .appendSuffix("day", "days")
                .toFormatter();
    }

Answer 1

我认为这是不可能的。根据JodaTime's javadoc , appendSuffix 方法将在没有字段附加后缀时抛出异常:

Throws: IllegalStateException - if no field exists to append to

所以我相信这次JodaTime帮不了你了。虽然，您可以这样做:

private String suffix(Period p) {
    int days = p.getDays();
    if (days <= 0) {
        return "";
    }

    return days == 1 ? "day" : "days";
}

使用此代码，以下内容:

System.out.println(suffix(Period.days(1)));
System.out.println(suffix(Period.days(2)));
System.out.println(suffix(new Period()));

产生输出:

day
days
// and a line with an empty string