Exception Handling - Absolute Java - page 576

updated result = 5.0
r
Final result = 5.0
Again? (y/n)
N
End of Program
7. A method that returns a special error code is usually better accomplished throwing an
exception instead. The following class maintains an account balance.
class Account
{
private double balance;
public Account()
{
balance = 0;
}
public Account( double initialDeposit)
{
balance = initialDeposit;
}
public double getBalance()
{

VideoNote

Solution to
Programming
Project 9.7

return balance;

}
// returns new balance or -1 if error
public double deposit( double amount)
{
if (amount > 0)
balance += amount;
else

return -1; // Code indicating error
return balance;
}
// returns new balance or -1 if invalid amount
public double withdraw(double amount)
{
if ((amount > balance) || (amount < 0))
return -1;
else
balance -= amount;
return balance;
}
}

Rewrite the class so that it throws appropriate exceptions instead of returning −1
as an error code. Write test code that attempts to withdraw and deposit invalid
amounts and catches the exceptions that are thrown.