Training: Java OOP

• In this course, you will explore the basics of inheritance and

• run-time polymorphism in Java, and how these concepts can be used
• to model Is-A relationships. Begin with an introduction to
• inheritance, and how to identify its advantages and applications.
• You will then apply inheritance to model real-world entities. Next,
• learn the concepts of polymorphism, its advantages and
• applications. Then move on to recognizing how the methods derived
• from java.lang.Object work, and also how all built-in Java classes
• possess the methods derived from java.lang.Object. You will examine
• how objects of derived classes have independent copies of member
• variables, even from the derived class. Following an introduction
• to the Is-A relationship, you will learn how to recognize, in
• single inheritance, that every object of the derived class is an
• object of the base class, but not every object of the base class is
• an object of the derived class. Explore how to upcast and downcast,
• and learn how downcasting can sometimes be dangerous. Finally,
• learn how one base class can be created with multiple derived
• classes.

• In this course, you will learn the role of constructors and how

• to use the super keyword in architecting inheritance hierarchies in
• Java. You will begin by identifying the role of access modifiers
• and recognizing the basics of superclass constructors. When you add
• your own constructor, you will see that Java takes away the default
• no-argument constructor it had provided. You will learn how to
• apply the two ways of initializing derived classes: implement an
• explicit no argument constructor in the base class or use the super
• keyword and have only parameterized constructors in both the base
• and derived classes. You will recognize that a base class's
• constructor is invoked when a derived class object is instantiated
• and identify what happens when there is a base and derived class
• that have many different constructors. You will be able to
• initialize member variables: add a member variable into a derived
• class and ensure it is correctly initialized, even in addition to
• any invocations of the base class constructor.

• In this course, you'll focus on the creation of multilevel

• inheritance in Java and how such hierarchies include child and
• grand-child classes that all inherit from a common ancestor base
• class. You'll explore various types of cast operations, how both
• upcast and downcast operations have their applications, and how
• downcast operations need to be performed with great care.

In this course, you'll learn about specific contrasts between run-time, compile-time polymorphism, and inheritance hierarchy in Java, including the use of the @Override annotation and type promotions in method overloading.

In this course, you'll learn about method overriding, including the use of the super keyword from contexts other than within constructors. You'll also examine the somewhat surprising behavior of static methods, owing to the fact that these are statically bound.

• 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.

In this course, you'll learn about access modifiers that can be used to tag member variables and member functions inside Java classes to regulate how these can be accessed from different contexts.

In this course, you'll learn about one of the most important concepts in all of object-oriented programming - the interface. You'll explore how anonymous inner classes provide lightweight instantiations of interfaces.