Why does SimpleDateFormat parse incorrect date?

Question

I have date in string format and I want to parse that into util date.

var date =\"03/11/2013\"

I am parsing this as :

new S         


        

Answer 1

You should use DateFormat.setLenient(false):

SimpleDateFormat df = new SimpleDateFormat("MM/dd/yyyy");
df.setLenient(false);
df.parse("03/88/2013"); // Throws an exception

I'm not sure that will catch everything you want - I seem to remember that even with setLenient(false) it's more lenient than you might expect - but it should catch invalid month numbers for example.

I don't think it will catch trailing text, e.g. "03/01/2013 sjsjsj". You could potentially use the overload of parse which accepts a ParsePosition, then check the current parse index after parsing has completed:

ParsePosition position = new ParsePosition(0);
Date date = dateFormat.parse(text, position);
if (position.getIndex() != text.length()) {
    // Throw an exception or whatever else you want to do
}

You should also look at the Joda Time API which may well allow for a stricter interpretation - and is a generally cleaner date/time API anyway.