This example checks if a String is a valid date by parsing the String with an instance
of the SimpleDateFormat class and returns true or false.

import java.text.SimpleDateFormat;
import java.text.ParseException;

public class DateTest {

  public boolean isValidDate(String inDate) {

    if (inDate == null)
      return false;

    //set the format to use as a constructor argument
    SimpleDateFormat dateFormat = new SimpleDateFormat(“yyyy-MM-dd”);
    
    if (inDate.trim().length() != dateFormat.toPattern().length())
      return false;

    dateFormat.setLenient(false);
    
    try {
      //parse the inDate parameter
      dateFormat.parse(inDate.trim());
    }
    catch (ParseException pe) {
      return false;
    }
    return true;
  }

  public static void main(String[] args) {

    DateTest test = new DateTest();

    System.out.println(test.isValidDate(“2004-02-29″));
    System.out.println(test.isValidDate(“2005-02-29″));
  }
}