Program: How to validate password using regular expression?

The below given example shows how to validate a password using regular expression. Here this regular expression allows must contain one digit, one lower case char, one upper case char, some special chars, length should be within 6 to 15 chars.

package com.java2novice.regex;

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class MyPasswordValidate {

private static Pattern pswNamePtrn = 
		Pattern.compile("((?=.*\\d)(?=.*[a-z])(?=.*[A-Z])(?=.*[@#$%]).{6,15})");
	
	public static boolean validatePassword(String userName){
		
		Matcher mtch = pswNamePtrn.matcher(userName);
		if(mtch.matches()){
			return true;
		}
		return false;
	}
	
	public static void main(String a[]){
		System.out.println("Is 'java2novice' a valid password? "
							+validatePassword("java2novice"));
		System.out.println("Is 'gabbarsingh' a valid password? "
							+validatePassword("gabbarsingh"));
		System.out.println("Is 'Java2NOVICE$' a valid password? "
							+validatePassword("Java2NOVICE$"));
		System.out.println("Is '234aBc#' a valid password? "
							+validatePassword("234aBc#"));
	}
}

Is 'java2novice' a valid password? false
Is 'gabbarsingh' a valid password? false
Is 'Java2NOVICE$' a valid password? true
Is '234aBc#' a valid password? true