look at this code :
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;
}
The regex2two
has been used to add a leading zero0
to 1-digit numbers. you can try this demo.
In the regexMap
I'v stored all 7 cases and appropriate regex-replace.