Summary HW6 Account Management In HW4 you kept track of mult

Summary

HW6: Account Management

In HW4, you kept track of multiple usernames and its associated password using arrays. However, usernames and passwords are typically part of a “User” object which in turn may be part of an “Account” object. Accounts also typically require a certain level of security beyond the typical encryption mechanisms. This assignment goes deeper into the concept of OOP as you create objects that requires proper rules and scope for correct usage.

Aside: As with Item objects from HW5, Account and User data is typically stored in databases.

Skills Expected

? All the skills from previous Assignment(s)

? Accessors/Mutators

? Overriding methods: equals and toString

Assignment Description

You will write three Class objects and a Driver for each class (i.e. submit six .java files):

? User
? Account
? AccountList

Note: All properties MUST be private

Submission Requirement: The Driver Class

? Each Class designed MUST be submitted with a corresponding “Driver” Class

? The Driver Class should have a main() that demonstrates, at minimum

o Calling the appropriate constructor to create the appropriate instance

o Everyproperty(instancevariables)canbesetandgetcorrectly(whereallowed) ? Every public method can be called successfully (and return the correct result)

Class Design: User

The User class is intended to be an abstract and simplified representation of a user

Class Properties

? First Name (String)

? Last Name (String)

? Username (String)

? Password (String)

Class Invariant

? First and Last Name must not be empty

? Username must be at least four characters long

? Password must be at least four characters long (is this a good invariant?)

Class Components

? A constructor that sets the initial user data (first name, last name, username, password)

? A getter/setter for each properties set out above

? A toString() method

? An equals() method

Class Design: Account

The Account class is intended to be an abstract and simplified representation of an account

Class Properties

? User (User)

? Balance (double) – represents how much money the user has in the account

Class Invariant

? Must be a valid account

? Balance must not be negative

Class Components

? A constructor that sets the initial User instance and balance amount

? A Getter but not a Setter for the each properties set out above (why?)

? A public method to add to the balance

? A public method to withdraw from the balance

? A toString() method

? An equals() method

Class Design: AccountList

The AccountList class is intended to be an abstract and simplified representation of a list of accounts.

Class Properties

? Accounts (an array of Account objects – or ArrayList) o No getters or setters* (do you know why?)

Class Invariant

? Can’t have multiple accounts with the same username

Class Components

? A public method that adds new accounts

? A public (boolean) method that determines whether an account with a given username exists in

the list

Grading Criteria

? User class object
o [2 points] Implements all required properties

? [2 points] Implements appropriate getters/setters
o [2points]Allinvariantsproperlyenforced
o [2points]Requiredclasscomponentsproperlyimplemented o [2points]Driverclassrequirementsaremet

? Account class object
o [2 points] Implements all required properties

? [1 point] Implements appropriate getters
o [2 points] All invariants properly enforced
o [2points]Requiredclasscomponentsproperlyimplemented o [2points]Driverclassrequirementsaremet

? AccountList class object
o [2 points] Implements all required properties
o [2 points] All invariants properly enforced
o [2points]Requiredclasscomponentsproperlyimplemented o [2points]Driverclassrequirementsaremet

? [1 point] Method JavaDoc: description, @param, @return

? [1 Point] Descriptive variable names

? [1 Point] Appropriate class header comment block

output

User

account

accountlist

Bluel: Terminal Window - HW6 Options toString: Name: Doe, John0 getUsername: joe0 getPassword: 1234 Changing firstName to Jane Changing lastName to Dae Changing username to jodie Changing password to supersecret toString: Name:Dae, Jane getUsername: jodie getPas3word: supersecret Comparison with itself: true

Solution

public class User {
   private String firstName;
   private String lastName;
   private String userName;
   private String Password;

   /**
   * @param firstName
   * @param lastName
   * @param userName
   * @param password
   */
   public User(String firstName, String lastName, String userName,
           String password) {

       try {
           setFirstName(firstName);
           setLastName(lastName);
           setUserName(userName);
           setPassword(password);
       } catch (NoSuchFieldException e) {
           // TODO Auto-generated catch block
           e.printStackTrace();
       }

   }

   /**
   * @return the firstName
   */
   public String getFirstName() {
       return firstName;
   }

   /**
   * @param firstName
   * the firstName to set
   * @throws NoSuchFieldException
   */
   public void setFirstName(String firstName) throws NoSuchFieldException {
       if (firstName.length() == 0)
           throw new NoSuchFieldException(\"first Name should not empty\");
       else
           this.firstName = firstName;
   }

   /**
   * @return the lastName
   */
   public String getLastName() {
       return lastName;
   }

   /**
   * @param lastName
   * the lastName to set
   * @throws NoSuchFieldException
   */
   public void setLastName(String lastName) throws NoSuchFieldException {
       if (lastName.length() == 0)
           throw new NoSuchFieldException(\"last Name should not empty\");
       else
           this.lastName = lastName;
   }

   /**
   * @return the userName
   */
   public String getUserName() {
       return userName;
   }

   /**
   * @param userName
   * the userName to set
   * @throws NoSuchFieldException
   */
   public void setUserName(String userName) throws NoSuchFieldException {
       if (userName.length() < 4)
           throw new NoSuchFieldException(
                   \"user name should contain atleas 4 characters\");
       else
           this.userName = userName;
   }

   /**
   * @return the password
   */
   public String getPassword() {

       return Password;
   }

   /**
   * @param password
   * the password to set
   * @throws NoSuchFieldException
   */
   public void setPassword(String password) throws NoSuchFieldException {
       if (password.length() < 4)
           throw new NoSuchFieldException(
                   \"password should contain atleas 4 characters\");
       else
           this.Password = password;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#hashCode()
   */
   @Override
   public int hashCode() {
       final int prime = 31;
       int result = 1;
       result = prime * result
               + ((Password == null) ? 0 : Password.hashCode());
       result = prime * result
               + ((firstName == null) ? 0 : firstName.hashCode());
       result = prime * result
               + ((lastName == null) ? 0 : lastName.hashCode());
       result = prime * result
               + ((userName == null) ? 0 : userName.hashCode());
       return result;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#equals(java.lang.Object)
   */
   @Override
   public boolean equals(Object obj) {
       if (this == obj)
           return true;
       if (obj == null)
           return false;
       if (getClass() != obj.getClass())
           return false;
       User other = (User) obj;
       if (Password == null) {
           if (other.Password != null)
               return false;
       } else if (!Password.equals(other.Password))
           return false;
       if (firstName == null) {
           if (other.firstName != null)
               return false;
       } else if (!firstName.equals(other.firstName))
           return false;
       if (lastName == null) {
           if (other.lastName != null)
               return false;
       } else if (!lastName.equals(other.lastName))
           return false;
       if (userName == null) {
           if (other.userName != null)
               return false;
       } else if (!userName.equals(other.userName))
           return false;
       return true;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#toString()
   */
   @Override
   public String toString() {
       return \"Name=\" + firstName + \", \" + lastName + \", userName=\" + userName;
   }

}
public class Account {

   private User user;
   private double balance;

   /**
   * @param user
   * @param balance
   */
   public Account(User user, double balance) {

       try {
           setUser(user);
           setBalance(balance);
       } catch (NoSuchFieldException e) {
           // TODO Auto-generated catch block
           e.printStackTrace();
       }
   }

   /**
   * @return the user
   */
   public User getUser() {
       return user;
   }

   /**
   * @param user
   * the user to set
   */
   private void setUser(User user) {
       this.user = user;
   }

   /**
   * @return the balance
   */
   public double getBalance() {
       return balance;
   }

   /**
   * @param balance
   * the balance to set
   * @throws NoSuchFieldException
   */
   private void setBalance(double balance) throws NoSuchFieldException {
       if (balance < 0)
           throw new NoSuchFieldException(\"balance cannot be negative\");
       else
           this.balance = balance;
   }

   /**
   * @param amount
   * @throws NoSuchFieldException
   */
   public void diposit(double amount) throws NoSuchFieldException {

       if (amount < 0)
           throw new NoSuchFieldException(\"amount cannot be negative\");
       else
           this.balance += amount;
   }

   /**
   * @param amount
   * @throws NoSuchFieldException
   */
   public void withdraw(double amount) throws NoSuchFieldException {

       if (amount < 0)
           throw new NoSuchFieldException(\"amount cannot be negative\");
       else
           this.balance -= amount;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#hashCode()
   */
   @Override
   public int hashCode() {
       final int prime = 31;
       int result = 1;
       long temp;
       temp = Double.doubleToLongBits(balance);
       result = prime * result + (int) (temp ^ (temp >>> 32));
       result = prime * result + ((user == null) ? 0 : user.hashCode());
       return result;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#equals(java.lang.Object)
   */
   @Override
   public boolean equals(Object obj) {
       if (this == obj)
           return true;
       if (obj == null)
           return false;
       if (getClass() != obj.getClass())
           return false;
       Account other = (Account) obj;
       if (Double.doubleToLongBits(balance) != Double
               .doubleToLongBits(other.balance))
           return false;
       if (user == null) {
           if (other.user != null)
               return false;
       } else if (!user.equals(other.user))
           return false;
       return true;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#toString()
   */
   @Override
   public String toString() {
       return \"Account [user=\" + user + \", balance=\" + balance + \"]\ \";
   }

}
import java.util.ArrayList;
import java.util.List;

public class AccountList {

   List<Account> accounts;

   /**
   *
   */
   public AccountList() {
       // TODO Auto-generated constructor stub
       accounts = new ArrayList<Account>();
   }

   /**
   * @param account
   */
   public void addAccount(Account account) {

       accounts.add(account);

   }

   /**
   * @param username
   * @return
   */
   public boolean checkAccount(String username) {

       for (int i = 0; i < accounts.size(); i++) {

           if (accounts.get(i).getUser().getUserName().equals(username))
               return true;
       }
       return false;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#hashCode()
   */
   @Override
   public int hashCode() {
       final int prime = 31;
       int result = 1;
       result = prime * result
               + ((accounts == null) ? 0 : accounts.hashCode());
       return result;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#equals(java.lang.Object)
   */
   @Override
   public boolean equals(Object obj) {
       if (this == obj)
           return true;
       if (obj == null)
           return false;
       if (getClass() != obj.getClass())
           return false;
       AccountList other = (AccountList) obj;
       if (accounts == null) {
           if (other.accounts != null)
               return false;
       } else if (!accounts.equals(other.accounts))
           return false;
       return true;
   }

   /*
   * (non-Javadoc)
   *
   * @see java.lang.Object#toString()
   */
   @Override
   public String toString() {
       return \"AccountList [accounts=\" + accounts + \"]\";
   }

}

public class TestUser {

   public static void main(String[] args) throws NoSuchFieldException {

       User user1 = new User(\"John0\", \"Doe\", \"joe0\", \"1234\");
       System.out.println(\"getUserName:\" + user1.getUserName());
       System.out.println(\"getPassword:\" + user1.getPassword());

       System.out.println(\"changing firstname to Jane\");
       user1.setFirstName(\"Jane\");

       System.out.println(\"changing lastname to Dae\");
       user1.setFirstName(\"Dae\");

       System.out.println(\"changing username to jodie\");
       user1.setUserName(\"jodie\");

       System.out.println(\"changing password to supersecret\");
       user1.setPassword(\"supersecret\");

       System.out.println(\"getUserName:\" + user1.getUserName());
       System.out.println(\"getPassword:\" + user1.getPassword());

       System.out.println(\"Comparison with itself :\" + user1.equals(user1));

   }
}

OUTPUT 1 :
getUserName:joe0
getPassword:1234
changing firstname to Jane
changing lastname to Dae
changing username to jodie
changing password to supersecret
getUserName:jodie
getPassword:supersecret
Comparison with itself :true

public class TestAccount {

   public static void main(String[] args) {

       try {
           User user1 = new User(\"John0\", \"Doe\", \"joe0\", \"1234\");

           Account account = new Account(user1, 100);
           System.out.println(\"toString :\" + account.toString());
           System.out.println(\"getUser() toString :\"
                   + account.getUser().toString());
           System.out.println(\"getBalance():\" + account.getBalance());
           System.out.println(\"Deposit 50\");
           account.diposit(50);
           System.out.println(\"toString :\" + account.toString());

           System.out.println(\"withdraw 110\");
           account.withdraw(110);
           System.out.println(\"toString :\" + account.toString());

           System.out.println(\"Comparison with itself :\"
                   + account.equals(account));

       } catch (Exception e) {
           // TODO: handle exception
       }
   }
}

OUTPUT 2:
toString :Account [user=Name=John0, Doe, userName=joe0, balance=100.0]

getUser() toString :Name=John0, Doe, userName=joe0
getBalance():100.0
Deposit 50
toString :Account [user=Name=John0, Doe, userName=joe0, balance=150.0]

withdraw 110
toString :Account [user=Name=John0, Doe, userName=joe0, balance=40.0]

Comparison with itself :true

public class TestAccountList {

   public static void main(String[] args) {

       AccountList accountList = new AccountList();
       User user1 = new User(\"John0\", \"Doe\", \"joe0\", \"1234\");
       User user2 = new User(\"John1\", \"Doe\", \"joe0\", \"1234\");
       User user3 = new User(\"John2\", \"Doe\", \"joe0\", \"1234\");
       User user4 = new User(\"John3\", \"Doe\", \"joe0\", \"1234\");
       User user5 = new User(\"John4\", \"Doe\", \"joe0\", \"1234\");

       accountList.addAccount(new Account(user1, 100));
       accountList.addAccount(new Account(user2, 200));
       accountList.addAccount(new Account(user3, 300));
       accountList.addAccount(new Account(user4, 400));
       accountList.addAccount(new Account(user5, 500));

       System.out.println(accountList);
       System.out.println(\"Comparison with itself :\"
               + accountList.equals(accountList));
   }

}
OUTPUT 3:
AccountList [accounts=[Account [user=Name=John0, Doe, userName=joe0, balance=100.0]
, Account [user=Name=John1, Doe, userName=joe0, balance=200.0]
, Account [user=Name=John2, Doe, userName=joe0, balance=300.0]
, Account [user=Name=John3, Doe, userName=joe0, balance=400.0]
, Account [user=Name=John4, Doe, userName=joe0, balance=500.0]
]]
Comparison with itself :true