Need regex for password validation with special characters as optional criteria: java

Question

i need a regex which must match below conditions

Condition 1: Atleast 1 uppercase alphabet
Condition 2: Atleast 1 lowercase alphabet
Condition 3: Atleast 1 digit
Condition 4: Special characters are optional, but if special characters exists in input string, then it must be among these characters: :.;,?!/\\_-()][#"'&$*%+=}{

Below program satisfies Condition 1,Condition 2,Condition 3 but not Condition 4

For Condition 4 this regex checks for atleast 1 special characters, i want this check to be optional.

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

public class PasswordValidation {
    public static void main(String[] args) {
        // TODO Auto-generated method stub
        String loginpwd = "sssaQjs#d123";
        String LOGIN_PASSWORD_VALIDATION = "(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?=.*[\\\\!\"#$%&()*+,./:;=?\\[\\]_{}])(?=\\S+$).{8,15}";
        Pattern password_Pattern = Pattern.compile(LOGIN_PASSWORD_VALIDATION);
        Matcher password_matcher = password_Pattern.matcher(loginpwd);      

        if(password_matcher.matches())
            System.out.println("match");
        else
            System.out.println("doesnot match");
    }
}

Answer 1

public static void main(String[] args) {
    // TODO Auto-generated method stub
    String password = "sssaQjs#d123";
    boolean hasUppercase = !password.equals(password.toLowerCase());
    boolean hasLowercase = !password.equals(password.toUpperCase());
    boolean hasDigit = password.matches(".*[0-9].*");
    boolean hasSpecial = password.matches(".*<all special characters escaped as alternative>.*");

    if(hasUppercase && hasLowercase && hasDigit && hasSpecial)
        System.out.println("match");
    else
        System.out.println("doesnot match");
}

Answer 2

Adding the three character classes to the character class of special characters would do it as in

String LOGIN_PASSWORD_VALIDATION = "(?=.*[0-9])(?=.*[a-z])(?=.*[A-Z])(?!.*[^\\\\!\"#$%&()*+,./:;=?\\[\\]_{}A-Za-z0-9])\\S{8,15}";

It asserts that there isn't a character outside the [\\\\\\\\!\\"#$%&()*+,./:;=?\\\\[\\\\]_{}A-Za-z0-9] class. Note the negative look ahead.

Since the character class has letters and digits included, it makes the special characters optional.