# L06 - Bank Account Lab

In this lab, we'll implement three classes: `BankAccount`, `CheckingAccount`, and `BankAccountTest`. As we write these classes, we will be taking advantage of Java's inheritance and polymorphism capabilities to make our job easier. 

### BankAccount Class 
This is the parent class. The `CheckingAccount` will be derived from this class. 

[![picture1.jpg](https://wiki.parts3492.org/uploads/images/gallery/2025-04/scaled-1680-/picture1.jpg)](https://wiki.parts3492.org/uploads/images/gallery/2025-04/picture1.jpg)

#### Member variables 
`double balance` 

#### Constructors 
`public BankAccount()`
- creates a `BankAccount` with a zero balance
  
`public BankAccount(double initialBalance)` 
- creates a BankAccount with a value of initial balance 
##### Methods 
`public void deposit(double amount)` 
- increases the balance by amount
  
`public void withdraw(double amount)` 
- decreases the balance by amount
  
`public double getBalance()` 
- returns the current balance 

#### BankAccount.java 
Download this file from Drive, it’s in L06F.zip and fill in the blanks with the missing code. 
```
/**
Parent BankAccount class 
@author __________ 
@version __________
*/
public class BankAccount { 
  __________ double balance;
   
  public BankAccount(){ 
    balance = 0; 
  } 
  
  public BankAccount(double initialBalance) { 
    balance = __________; 
  }
   
  public __________ deposit(double amount) { 
    balance = __________ + amount; 
  } 
  
  
  public void withdraw(double amount) { 
    balance = __________ - amount; 
  } 
  
  public double getBalance() {
    return __________;
  }
}
```

### CheckingAccount Class 
This class extends the BankAccount class. 

#### Member variables 
`int transactionCount`
- the number of transactions accumulated over a month 

#### Constructors 
`public CheckingAccount()`
- creates a checking account with a zero balance and sets transactionCount to zero.
  
`public CheckingAccount(double initialBalance)` 
- creates a checking account and with a balance of initialBalance and sets transactionCount to zero. 

#### Methods 
`public void deposit(double amount)` 
- increases the balance by amount and increases the transactionCount by 1.
   
`public void withdraw(double amount)` 
- decreases the balance by amount and increases the transactionCount by 1.
   
`public void deductFees()` 
- deducts the accumulated transaction fees and resets the transactionCount to 0. If there are more than three transactions, then the fee is equal to 2.00*(transactionCount – 3). Note that the first three transactions are free and that the fee per transaction is $2.00. 

#### CheckingAccount.java 
Download this file from Drive, it’s in L06F.zip and fill in the blanks with the missing code. 
```
/**
Child CheckingAccount class
@author __________
@version __________
*/
public class CheckingAccount __________ BankAccount { 
  __________ int transactionCount; 
  
  public CheckingAccount() { 
    transactionCount = 0; 
  } 
  
  public CheckingAccount(double initialBalance) { 
    super(__________); 
    //use the super class constructor that's already coded 
    transactionCount = 0; 
  } 
  
  public __________ deposit(double amount) { 
    super.deposit(amount); 
    transactionCount = __________ + 1; 
  } 
  
  public void withdraw(double amount) { 
    __________.withdraw(amount); 
    transactionCount = __________ + 1; 
  }
  
  public void deductFees() { 
    if (transactionCount > 3) { 
      double fee = 2.0*(transactionCount – 3); 
      __________.withdraw(fee); 
    } 
    transactionCount = 0; 
  } 
} 
```

### Testing Our Classes 
To test our two classes, we'll write a BankAccountTest class that performs the following: 
- Instantiates a checking account with an initial balance specified by the user 
- Presents a menu with the following options: 
  - D - Deposit money into the checking account (prompt the user for amount) 
  - W - Withdraw money from the checking account (prompt user for amount) 
  - P - Process end-of-month activities (withdraw fees for the checking account) 
  - S - Show the current checking account balance 
  - E - Exit the program
 
### BankAccountTest.java 
Download this file from Drive, it’s in L06F.zip and fill in the blanks with the missing code. 
```
import java.util.*;
/**
BankAccount test class 
@author __________
@version __________
*/
public class BankAccountTest { 
  public static void main(String[] args) { 
    Scanner myScanner = new Scanner(System.in); 
    System.out.print("Enter initial checking account balance: ");
    double amount = Double.parseDouble(myScanner.nextLine());
    CheckingAccount myChecking = new CheckingAccount(amount);
     
    System.out.println("D - Deposit into checking");
    System.out.println("W - Withdraw from checking");
    System.out.println("P - End of month processing");
    System.out.println("S - Show account balance");
    System.out.println("E - Exit the program"); 
    
    boolean done = false; 
    
    while (!done) {
      System.out.print("> "); 
      String choice = myScanner.nextLine(); 
      
      if (choice.equalsIgnoreCase("D")) {
        System.out.print("Enter amount to deposit: "); 
        amount = Double.parseDouble(myScanner.nextLine());
        myChecking.deposit(amount); 
      }
      else if (choice.equalsIgnoreCase("W")) { 
        System.out.print("Enter amount to withdraw: "); 
        amount = Double.parseDouble(myScanner.nextLine());
        myChecking.withdraw(amount); 
      } 
      else if (choice.equalsIgnoreCase("P")) 
        myChecking.deductFees(); 
      else if (choice.equalsIgnoreCase("S"))
        System.out.println("Checking balance: " + myChecking.getBalance()); 
      else if (choice.equalsIgnoreCase("E")) 
        done = true; 
      else 
        System.out.println("Invalid menu choice - please re-enter"); 
    }
      
    System.out.println("Goodbye!"); 
  } 
} 
```