- class Animal {}
- class Dog extends Animal{}
- class Cat extends Animal{}
- class GenericDemo {
- public static void main(String[] args) {
- Collection<Object> c = new ArrayList<Object>();
- Collection<Animal> c1 = new ArrayList<Animal>();
- Collection<Animal> c2 = new ArrayList<Dog>();
- Collection<Animal> c3 = new ArrayList<Cat>();
- Collection<? extends Animal> c4 = new ArrayList<Object>();
- Collection<? extends Animal> c5 = new ArrayList<Animal>();
- Collection<? extends Animal> c6 = new ArrayList<Dog>();
- Collection<? extends Animal> c7 = new ArrayList<Cat>();
- Collection<? super Animal> c8 = new ArrayList<Object>();
- Collection<? super Animal> c9 = new ArrayList<Animal>();
- Collection<? super Animal> c10 = new ArrayList<Dog>();
- Collection<? super Animal> c11 = new ArrayList<Cat>();
- }
- }
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