Generics Summary

Generic Classes

1. class MyClass <T> { … }
2. class MyClass <T,V> { … }
3. class MyClass <T> implements SomeInterface<T> { … }
4. class MyClass <T> extends SomeClass { … }
5. class MyClass <T> extends GenericClass <T> { … }
6. class MyClass <T,V> extends GenericClass <T> implements SomeInterface<V> { … }
7. class MyClass <T> extends GenericClass <T> implements SomeInterface<String> { … }
8. class MyClass <T,V> extends GenericClass <T> implements SomeInterface<V>, OtherInterface { … }

9. class MyClass <T extends SomeClass> { … }
10. class MyClass <T extends SomeClass & SomeInterface> { … }
11. class MyClass <T extends SomeClass & SomeInterface & OtherInterface> { … }

Generic Interfaces

1. interface MyInterface <T> { … }
2. interface MyInterface <T extends Comparable<T>> { … }

Generic Constructors in Non-Generic Classes

1. <T> MyConstructor (T obj) { … }
2. <T extends SomeClass> MyConstructor (T obj) { … }

Generic Methods in Non-Generic Classes

1. <T> void foo(T obj){ … }
2. <T> void foo(T obj1, T obj2) { … }
3. <T> T foo(T obj) { … }

4. <T extends SomeClass> void foo(T obj) { … }
5. <T extends Comparable<T>, V extends T> void foo(T obj1, V obj2) { … }
6. <T extends SomeClass, V extends T> void foo(GenClass<T> obj1, GenClass<V> obj2) { … }

Wildcards

4. GenericClass<?> field;
5. MyClass(GenericClass<?> obj) { … }
6. someType myMethod (GenericClass<?> obj) { … }
7. someType myMethod (GenericClass<? extends SuperClass> obj) { … }
8. someType myMethod (GenericClass<? super SubClass> obj) { … }

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