## BankAccount.java
public abstract class BankAccount {
public String toString() {
return this.getClass().toString();
}
}
## CheckingAccount.java
public class CheckingAccount extends BankAccount {
}
## SavingsAccount.java
public class SavingsAccount extends BankAccount {
}
## Main.java
public class Main {
public static void main(String[] args) {
BankAccount ca = new CheckingAccount();
BankAccount sa = new SavingsAccount();
System.out.println(ca);
System.out.println(sa);
}
}