在java中将Youtube Data API V3视频持续时间转换为hh:mm:ss格式？

Question

我正在使用 Youtube data api v3 获取视频信息，如标题、观看次数和持续时间。持续时间值对我来说是新的，因为ISO8601 date我需要将其转换为可读格式，如 hh:mm:ss。持续时间可以有以下不同的值：

1. PT1S --> 00:01
2. PT1M --> 01:00
3. PT1H --> 01:00:00
4. PT1M1S --> 01:01
5. PT1H1S --> 01:00:01
6. PT1H1M1S --> 01:01:01

我可以使用Joda Time 库来解析该值并计算以秒为单位的持续时间，但该库的大小为 500kb，这会增加我不想要的应用程序的大小。

Answer 1

看看这段代码：

private static HashMap<String, String> regexMap = new HashMap<>();
private static String regex2two = "(?<=[^\\d])(\\d)(?=[^\\d])";
private static String two = "0$1";

public static void main(String[] args) {

    regexMap.put("PT(\\d\\d)S", "00:$1");
    regexMap.put("PT(\\d\\d)M", "$1:00");
    regexMap.put("PT(\\d\\d)H", "$1:00:00");
    regexMap.put("PT(\\d\\d)M(\\d\\d)S", "$1:$2");
    regexMap.put("PT(\\d\\d)H(\\d\\d)S", "$1:00:$2");
    regexMap.put("PT(\\d\\d)H(\\d\\d)M", "$1:$2:00");
    regexMap.put("PT(\\d\\d)H(\\d\\d)M(\\d\\d)S", "$1:$2:$3");

    String[] dates = { "PT1S", "PT1M", "PT1H", "PT1M1S", "PT1H1S", "PT1H1M", "PT1H1M1S", "PT10H1M13S", "PT10H1S", "PT1M11S" };

    for (String date : dates) {
        String d = date.replaceAll(regex2two, two);
        String regex = getRegex(d);
        if (regex == null) {
            System.out.println(d + ": invalid");
            continue;
        }
        String newDate = d.replaceAll(regex, regexMap.get(regex));
        System.out.println(date + " : " +newDate);
    }    
}

private static String getRegex(String date) {
    for (String r : regexMap.keySet())
        if (Pattern.matches(r, date))
            return r;
    return null;
}

用于regex2two将前导零添加0到 1 位数字。你可以试试这个演示。

在regexMap我存储了所有 7 个案例和适当的正则表达式替换。