import java.text.NumberFormat;
// 1. ***** indicate that SavingsAccount inherits
// from BankAccount
public class SavingsAccount
{
public final double DEFAULT_RATE = .03;
// 2. ****** define the private interestRate instance variable
// interestRate, a double, represents an annual rate
// Part 2 student code starts here:
private double interestRate;
// Part 2 student code ends here.
// 3 ***** write the default constructor
/** default constructor
* explicitly calls the BankAccount default constructor
* set interestRate to default value DEFAULT_RATE
* print a message to System.out indicating that
* constructor is called
*/
// Part 3 student code starts here:
public void BankAccount()
{
interestRate = DEFAULT_RATE;
System.out.println("Default constructor is called. ");
}
// Part 3 student code ends here.
// 4 ***** write the overloaded constructor
/** overloaded constructor
* explicitly call BankAccount overloaded constructor
* call setInterestRate method, passing startInterestRate
* print a message to System.out indicating that
* constructor is called
* @param startBalance starting balance
* @param startInterestRate starting interest rate
*/
// Part 4 student code starts here:
public void BankAccount(double startBalance,double startInterestRate)
{
setInterestRate(startInterestRate);
System.out.println("Overloaded constructor is called. ");
}
// Part 4 student code ends here.
// 5 ****** write this method:
/** applyInterest method, no parameters, void return value
* call deposit method, passing a month's worth of interest
* remember that interestRate instance variable is annual rate
*/
// Part 5 student code starts here:
public void applyInterest()
{
deposit ( super.getBalance() * (interestRate / 12.0));
}
// Part 5 student code ends here.
/** accessor method for interestRate
* @return interestRate
*/
public double getInterestRate()
{
return interestRate;
}
/** mutator method for interestRate
* @param newInterestRate new value for interestRate
* newInterestRate must be >= 0.0
* if not, print an error message
*/
public void setInterestRate(double newInterestRate)
{
if (newInterestRate >= 0.0)
{
interestRate = newInterestRate;
}
else
{
System.err.println("Interest rate cannot be negative");
}
}
// 6 ***** write this method
/* toString method
* @return String containing formatted balance and interestRate
* invokes superclass toString to format balance
* formats interestRate as percent using a NumberFormat object
* To create a NumberFormat object for formatting percentages
* use the getPercentInstance method in the NumberFormat class,
* which has this API:
* static NumberFormat getPercentInstance( )
*/
// Part 6 student code starts here:
public String toString()
{
NumberFormat percent = NumberFormat.getPercentInstance();
return super.toString()
+ "\n" + "interestRate is " + percent.format(interestRate);
}
// Part 6 student code ends here.
}
So far, I am having trouble with part 5. For starters, this is not stand alone code. It is a larger part of a bank account program. The 'teller' part is the code that is actually run.
My problem is I cannot get 'SavingsAccount' to clean compile. No process I try for part 5 works. It says it cannot read the symbol, but I'm not sure how exactly it can be wrong. I also compiled the 'teller' file, but it won't compile without quite a few errors. The biggest being that it can't find classes and symbols that I haven't touched in the first place. I'm not sure if that is due to the fact I haven't got SavingsAccount to compile cleanly or not.
COMPILER ERROR: Activity-10-1\\SavingsAccount.java:68: error: cannot find symbol deposit (getBalance() * (interestRate / 12.0)); ^ symbol: method getBalance() location: class SavingsAccount 1 error
Tool completed with exit code 1
You need to get step 1 done before step 5 will work. As it stands, SavingsAccount
inherits from Object
, not from BankAccount
. Try changing
public class SavingsAccount
to
public class SavingsAccount extends BankAccount
At that point, the getBalance()
method (which I'm guessing is defined in the BankAccount
class) should become accessible.
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