In this course, participants learn about two specific and important aspects of Java—the final and abstract keywords. The final keyword can be used to mark member variables, member functions, and even entire classes, with different meanings in each context. You will discover how to mark variables as final, and the implications of doing so. Learn how to correctly instantiate final arrays. Remember that arrays are reference types, pointing to a block of memory, and remember that once an array has been marked as final, it can only be initialized once. Discover how to create and use final classes and final methods. Final classes cannot be extended. You will learn to recognize the implications of defining a class as abstract. Also, learn how to extend abstract classes and the implications of doing so. As the course concludes, you will discover that a class can only be instantiated if it has implemented all abstract methods.