Question

Create a simple Java class for a Password with the following requirements:

 This program will have a header block comment with your name, the course and section, as well as a brief description of what the class does.
 One String property: password (protected to only allow secure passwords)
o A secure password must be at least 8 characters in length
o A secure password must have three of the following four requirements:
 A lower case letter
 An upper case letter
 An integer digit (0-9)
 A keyboard producible symbol (e.g. $, @, |, >)
 A constructor that takes no arguments, and sets the password to: 1newPassword.
 A second constructor that takes in a String argument to set the initial password value for the Password object. Use data protection to ensure the user entered a secure password.
 A setPassword() method that takes in a String argument and uses data protection to ensure the user entered a secure password.
 A getPassword() method that returns the password as a String.
 A toString() method that returns the password as a String (it may call the getPassword() method).
 An equals() method that takes in another Password object as an argument, and then determines if the two objects have the same password value.
 All data protection will throw an appropriate Exception

Create a simple program using Java that demonstrates the Password class with the following requirements:

 Creates a Password object using the no argument constructor.
 Creates a second Password object using the constructor that takes in a String argument.
 Additionally, use either a do or while loop to get the user to enter a secure password using the setPassword() method on the 1st Password object. The loop will continue until they enter a valid secure Password.
 The program will display the password value for both of the objects using the toString() method.
 The program will indicate whether the two password values are the same using the equals() method.
 All thrown Exceptions will handled.

Answer 1

import java.util.Objects;

public class Password {
private String password;

Password(){
this.password = "1newPassword";
}

Password(String password){
int upper = 0, lower = 0, digit = 0, special = 0;
for(int i =0;i<password.length();i++){
char c = password.charAt(i);
if(Character.isUpperCase(c)){
upper++;
}
if(Character.isLowerCase(c)){
lower++;
}
if(Character.isDigit(c)){
digit++;
}
if(c>=33&&c<=46||c==64){
special++;
}
}
try {
if(special>=1&&lower>=1&&upper>=1&&digit>=1&&password.length() >= 8){
this.password = password;
}else if(special<1){
throw new IllegalArgumentException("Password must contain atleast one special character");
}else if(lower<1){
throw new IllegalArgumentException("Password must contain atleast one lower case letter");
}else if(upper<1){
throw new IllegalArgumentException("Password must contain atleast one upper case letter");
}else if(digit<1){
throw new IllegalArgumentException("Password must contain atleast one digit");
}
}catch (IllegalArgumentException e){
System.out.println(e);
}

}

public String getPassword() {
return password;
}

public void setPassword(String password) {
int upper = 0, lower = 0, digit = 0, special = 0;
for(int i =0;i<password.length();i++){
char c = password.charAt(i);
if(Character.isUpperCase(c)){
upper++;
}
if(Character.isLowerCase(c)){
lower++;
}
if(Character.isDigit(c)){
digit++;
}
if(c>=33&&c<=46||c==64){
special++;
}
}
try {
if(special>=1&&lower>=1&&upper>=1&&digit>=1&&password.length() >= 8){
this.password = password;
}else if(special<1){
throw new IllegalArgumentException("Password must contain atleast one special character");
}else if(lower<1){
throw new IllegalArgumentException("Password must contain atleast one lower case letter");
}else if(upper<1){
throw new IllegalArgumentException("Password must contain atleast one upper case letter");
}else if(digit<1){
throw new IllegalArgumentException("Password must contain atleast one digit");
}
}catch (IllegalArgumentException e){
System.out.println(e);
}
}

@Override
public String toString() {
return "Password: " + this.getPassword();
}

@Override
public boolean equals(Object o) {
if (this == o) return true;
if (o == null || getClass() != o.getClass()) return false;
Password password1 = (Password) o;
return Objects.equals(password, password1.password);
}

@Override
public int hashCode() {
return Objects.hash(password);
}
}
PasswordMain.java

import java.util.Scanner;

public class passwordMain {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
Password password = new Password();
Password password1 = new Password("NewPAssword12@");

String pass;
boolean status = false;
do{
System.out.println("Enter a Password");
pass = sc.next();
int upper = 0, lower = 0, digit = 0, special = 0;
for(int i =0;i<pass.length();i++){
char c = pass.charAt(i);
if(Character.isUpperCase(c)){
upper++;
}
if(Character.isLowerCase(c)){
lower++;
}
if(Character.isDigit(c)){
digit++;
}
if(c>=33&&c<=46||c==64){
special++;
}
}
if(special>=1&&lower>=1&&upper>=1&&digit>=1&&pass.length() >= 8){
status = true;
password.setPassword(pass);
}

}while (status == false);

if(password.equals(password1)){
System.out.println("Password are same");
}else {
System.out.println("Not Match");
}

System.out.println(password.toString());
System.out.println(password1.toString());

}
}
Output: