How to get the given date string format(pattern) in java?

Question

I want to get the format of a given date string.

Example: I have a string like 2011-09-27T07:04:21.97-05:00 and the date format of this string is yyyy-MM-dd'T'HH:mm:ss.SSS.

Here I want to find out this date format when I pass string(2011-09-27T07:04:21.97-05:00) to a method which will return the format(yyyy-MM-dd'T'HH:mm:ss.SSS), then later I will format my given date string according to my requirement(like yy-mm--dd or mm/dd/yyyy).

Can any one tell me how can I get it achieved?

Answer 1

import java.text.ParseException; import java.text.SimpleDateFormat; import java.util.Date; import java.util.regex.Matcher; import java.util.regex.Pattern;  public class NewClass {      private static final String[] formats = {                  "yyyy-MM-dd'T'HH:mm:ss'Z'",   "yyyy-MM-dd'T'HH:mm:ssZ",                 "yyyy-MM-dd'T'HH:mm:ss",      "yyyy-MM-dd'T'HH:mm:ss.SSS'Z'",                 "yyyy-MM-dd'T'HH:mm:ss.SSSZ", "yyyy-MM-dd HH:mm:ss",                  "MM/dd/yyyy HH:mm:ss",        "MM/dd/yyyy'T'HH:mm:ss.SSS'Z'",                  "MM/dd/yyyy'T'HH:mm:ss.SSSZ", "MM/dd/yyyy'T'HH:mm:ss.SSS",                  "MM/dd/yyyy'T'HH:mm:ssZ",     "MM/dd/yyyy'T'HH:mm:ss",                  "yyyy:MM:dd HH:mm:ss",        "yyyyMMdd", };          /*          * @param args          */     public static void main(String[] args) {         String yyyyMMdd = "20110917";            parse(yyyyMMdd);     }      public static void parse(String d) {         if (d != null) {             for (String parse : formats) {                 SimpleDateFormat sdf = new SimpleDateFormat(parse);                 try {                     sdf.parse(d);                     System.out.println("Printing the value of " + parse);                 } catch (ParseException e) {                  }             }         }     } } 

Answer 2

you can do like this way, I don't know good way or not but try this

first create the SimpleDateFormat object

SimpleDateFormt sdf = new SimpleDateFormat("yyyy-MM-dd 'T' HH:mm:ss.SSS"); 

now when check the date if this will parse in this format then change as per your format

try{      Date date = sdf.parse(yourdate);      sdf.applyPattern("yy-mm--dd or mm/dd/yyyy");      String dateformat = sdf.format(date); }catch(Exception ex) { // here forgot the exact exception class Parse exception was used     // do something here } 

updated post:

Returning a date format from an unknown format of date string in java

How to convert String to Date without knowing the format?

Parse any date in Java