Why Has No ParseException Exception in Parsing Date String?

Date/time converts to date string or vice versa. It is a common thing in our developer's life. For example,

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
import java.text.ParseException;

public class ConsoleInputExample  {

    public static void main(String[] args) {

        Scanner scanner= new Scanner(System.in);
        SimpleDateFormat df = new SimpleDateFormat("mm/dd/yyyy");
        
        try {
            do {
                System.out.print("ENTER DATE STRING (mm/dd/yyyy or 'q') : ");
                String dateString = scanner.next();
                if (dateString != null) dateString = dateString.trim();
                if (dateString == null || dateString.length()== 0)
                    continue;        
                if (dateString.equalsIgnoreCase("Q"))
                    break;
                
                // Parse the date
                try {
                  Date date = df.parse(dateString);
                  System.out.println("Original string: " + dateString);
                  System.out.println("Parsed date    : " + date.toString());
                  System.out.println();
                }
                catch(ParseException pe) {
                System.out.println("ERROR: could not parse date in string \""
                      + dateString + "\"");
                }
                
            } while (true);
        }
        catch(Exception e) {
            ;
        }
    }
}

Run the above code and enter wrong month, day, and year as following and you did not get ParseException:

ENTER DATE STRING (mm/dd/yyyy or 'q') : 2222/22232/23123123
Original string: 2222/22232/23123123
Parsed date    : Mon Nov 14 13:02:00 EST 23123183

Actually, SimpleDateFormat class provides setLenient method for valiadtion of the parsing date/time string. The following code is fine,

import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Scanner;
import java.text.ParseException;

public class ConsoleInputExample  {

    public static void main(String[] args) {

        Scanner scanner= new Scanner(System.in);
        SimpleDateFormat df = new SimpleDateFormat("mm/dd/yyyy");
        df.setLenient(false);
        
        try {
            do {
                System.out.print("ENTER DATE STRING (mm/dd/yyyy or 'q') : ");
                String dateString = scanner.next();
                if (dateString != null) dateString = dateString.trim();
                if (dateString == null || dateString.length()== 0)
                    continue;        
                if (dateString.equalsIgnoreCase("Q"))
                    break;
                
                // Parse the date
                try {
                  Date date = df.parse(dateString);
                  System.out.println("Original string: " + dateString);
                  System.out.println("Parsed date    : " + date.toString());
                  System.out.println();
                }
              catch(ParseException pe) {
                System.out.println("ERROR: could not parse date in string \""
                   + dateString + "\"");
                }
                
            } while (true);
        }
        catch(Exception e) {
            ;
        }
    }
}

Here is result,

ENTER DATE STRING (mm/dd/yyyy or 'q') : 2222/22232/23123123
ERROR: could not parse date in string "2222/22232/23123123"
ENTER DATE STRING (mm/dd/yyyy or 'q') : 

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