Use the following file:

BankAccountTester.java

public class BankAccountTester
{
   public static void main(String[] args)
   {
      BankAccount account = new BankAccount(100);
      account.deposit(-100);
      System.out.println(account.getBalance());
      System.out.println("Expected: 100");
      account.withdraw(-50);
      System.out.println(account.getBalance());
      System.out.println("Expected: 100");
      account.withdraw(200);
      System.out.println(account.getBalance());
      System.out.println("Expected: 100");      
   }
}