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1. #JAVA CONVERT STRING TO DATE FROM DIFFERENT FORMATS HOW TO#
2. #JAVA CONVERT STRING TO DATE FROM DIFFERENT FORMATS CODE#

Summary: Java SimpleDateFormat date formatting The important thing to note is that the program will stay in the for loop shown until either (a) the date given ( dateString) matches one of the given Java date formatting patterns, or (b) all the patterns have been exhausted, in which case the method returns a null Date reference. I tried to document this SimpleDateFormat example pretty well, so I don't have anything else to add to it at this time. we may miss on 99 format attempts, but match on one format, parse() will throw an exception if the given dateString doesn't match SimpleDateFormat dateFormat = new SimpleDateFormat(format) Public static Date parseDate(String dateString, String formats) * we could not match any of the known formats. * formats An array of date formats that we have allowed for. * dateString An input String, presumably from a user or a database table. Given that introduction, here's an example Java method named parseDate that attempts to convert a given Java String to a Date object using a given list of potential custom date formats:

I think this is a terrific approach, because it lets a user enter a date in a wide range of date formats, and then this method does the hard work of seeing if the date format they entered matches any of the date formats our program can handle.

#JAVA CONVERT STRING TO DATE FROM DIFFERENT FORMATS CODE#

In this example, I'm showing the source code for a Java method that attempts to parse a given Java String ( dateString) against an array of possible Java Date formatting patterns. Now that you've seen a simple example of how this Java SimpleDateFormat Date to String conversion works, lets take a look at a real world example of how you might convert a Date to a String, using an array (or List) of possible String date formatting patterns.

Bonus: Using an array of patterns in a SimpleDateFormat Date to String conversion If the SimpleDateFormat.parse method can parse the given String, it converts the String to a Date objectĪgain, just to drill this point home, the date format we're expecting (" MM/dd/yyyy") must match the format we're given (as it does in ""), otherwise the parse method will throw a ParseException.

If the SimpleDateFormat.parse method can't parse the given String, it will throw a ParseException.Attempt to parse a String that is supposed to contain a date in the format we expect.Craete a SimpleDateFormat instance, giving it the expected format.execution will come here if the String that is givenĪs you can see from that example, the steps to convert from a given Java String to Date using SimpleDateFormat are: (2) give the formatter a String that matches the SimpleDateFormat pattern SimpleDateFormat formatter = new SimpleDateFormat(expectedPattern) this is the format/pattern we're expecting to receive. (1) create a SimpleDateFormat object with the desired format. Public class SimpleDateFormatStringToDate * Uses a String pattern to define the expected date format. * Java SimpleDateFormat - convert a Java String to a Date

#JAVA CONVERT STRING TO DATE FROM DIFFERENT FORMATS HOW TO#

Here’s the source code for a complete SimpleDateFormat example that demonstrates how to convert from a given formatted Java String to a Date object: SimpleDateFormat: Java String to Date conversion In an earlier example I showed how to use the Java SimpleDateFormat class to convert from a Date to a String, but you can also use the SimpleDateFormat class to convert in the opposite direction, from a given Java String to a Date object. Summary: This is a Java SimpleDateFormat (date formatting) example, showing how to convert a String to a Date.