MyClass.j

@implementation MyClass : CPObject
{
}

- (CPString)helloWorld
{
  return @"Hello World"
}

@end

MyClassTest.j

@import "MyClass.j"

@implementation MyClassTest : OJTestCase

- (CPString)testHelloWorld
{
  var obj = [[MyClass alloc] init];
  [self assertTrue:(@"Hello World" === [obj helloWorld])];
}

@end