Prevent invalid date from getting converted into date of next month in jdk6?

Question

Consider the snippet:

String dateStr = "Mon Jan 32 00:00:00 IST 2015";    // 32 Jan 2015

DateFormat formatter = new SimpleDateFormat("E MMM dd HH:mm:ss Z yyyy");
DateFormat ddMMyyyy = new SimpleDateFormat("dd.MM.yyyy");
System.out.println(ddMMyyyy.format(formatter.parse(dateStr)));

gives me the output as

01.02.2015     //   Ist February 2015

I wish to prevent this to make the user aware on the UI that is an invalid date?
Any suggestions?

Answer 1

The option setLenient() of your SimpleDateFormat is what you are looking for.

After you set isLenient to false, it will only accept correctly formatted dates anymore, and throw a ParseException in other cases.

String dateStr = "Mon Jan 32 00:00:00 IST 2015";    // 32 Jan 2015

DateFormat formatter = new SimpleDateFormat("E MMM dd HH:mm:ss Z yyyy");
formatter.setLenient(false);
DateFormat ddMMyyyy = new SimpleDateFormat("dd.MM.yyyy");
try {
    System.out.println(ddMMyyyy.format(formatter.parse(dateStr)));
} catch (ParseException e) {
    // Your date is invalid
}

Answer 2

You can use DateFormat.setLenient(boolean) to (from the Javadoc) with strict parsing, inputs must match this object's format.

DateFormat ddMMyyyy = new SimpleDateFormat("dd.MM.yyyy");
ddMMyyyy.setLenient(false);