Problem formatting date.

Question

I have a problem in validating and formatting date input by the user. The user input format is dd-MM-yyyy. I have to validate it and format it to dd-MMM-yy format. I tried the below code.
import java.util.*;
import java.text.*;
public class DateFormatter{
     public static void main(String[] args){
          String str = "24-12-20gg";
          SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
          try{
               sdf.setLenient(false);
               Date date = sdf.parse(str);
               System.out.println(date);
          }catch(Exception e){
               System.out.println(e);
The above code parses the date as - Tue Dec 24 00:00:00 IST 0020 . I want to throw an exception if it is not a date and is not of four digits. Any solution ?.

Answer 1

Why not Java support such things. This will help to avoid reinventing the
wheel.Java does support such things; there is no need to reinvent the wheel. Example:
import java.text.*;
import java.util.*;
public class DateParseDemo {
    public static void main(String[] args) {
        new DateParseDemo().go();
    public void go() {
        String format = "dd-MM-yyyy";
        String goodDate = "24-12-2003";
        String badDate = "Dec 24, 2004";
        if (dateIsValid(format, goodDate)) {
            System.out.println("\"" + goodDate + "\" is valid!");
        if (!dateIsValid(format, badDate)) {
            System.out.println("\"" + badDate + "\" is NOT valid!");
    public boolean dateIsValid(String format, String date) {
        boolean valid = false;
        DateFormat df = new SimpleDateFormat(format);
        Date parsed;
        try {
            parsed = df.parse(date);
            valid = true;
        } catch (ParseException pe) {
            // log exception
        return valid;