OrderTester - Java Class For Internal Order

I have a problem where i have to run a test order on my internalOrder class from the orderTester class and I am not sure how to do this. This is the code i have for my orderTester class:

public static void testCase8(){
orders ords = new orders ("Pen", 8, -0.5);
System.out.println("Test Case 8:" + "
" + ords.getOrderDetails());

[Code] ....

this is the code for my Internal class

public InternalOrder(String productName,int quantity ){
super(productName, quantity,DISCOUNT); }
public void printInternalReport(){
System.out.println("Printing internal report ...");
}

Now my orderTest class is passed though orders class and intrenalOrder class if you need that code i will put it up.