Using inheritance with ArrayList

[neilcsmith]

@Sarah

void test(ArrayList<ObjectType1> object) { }

Try

void test(ArrayList<? extends ObjectType1> object) {

and welcome to the weird world of Java generics!

Inheritance doesn’t work the same way with generics - see Generics, Inheritance, and Subtypes (The Java™ Tutorials > Learning the Java Language > Generics (Updated))