如何从另一个类调用方法

Question

It has been a long time since I used java and I have run into a problem. I need to load test cases from a file and then run them. The problem is that I need to call a method "shippingCost" from another class "Function.class" This is a compiled code, no source.

How do I call this from my class, "FunctionTest.java" inside of the public static void main.

Thanks!

The class, and the error msg.

Answer 1

You don't need the source in order to call the method, all you need is the compiled class. As long as you can access the method (generally if it's public) then you should be able to call it. An IDE like eclipse will even be able to help you find out which methods are available on an instance of the class.

So in the simplest case, you just create an instance of the class and then call the method.

Function func = new Function();
func.callMethod();

Further help would be giving us the error message so we would know which type of problem you are actually having.

Answer 2

You need to get a reference to an instance of the object and invoke its methods.

Function function = new Function();
function.myFunction();

Your naming scheme leaves a lot to be desired.

Answer 3

1. Put the 'Function.class' file into the Libraries folder of your project.
2. Put an import statement with the correct package of 'Function' class into your FunctionTest.java file: import xx.xx.Function; (Netbeans should be able to do that automatically on command.)