Classes/Objects  «Prev  Next»
Lesson 11

Java Module Conclusion

The following list summarizes the important points that were covered in this module:
  1. A fully encapsulated class declares all of its variables as private and provides methods for getting and setting the properties represented by field variables.
  2. A non-inner class may specify the modifiers public, abstract, and final.
  3. A final class may not be extended.
  4. "is a" identifies subclass relationships, while "has a" identifies member variables.
  5. Constructors are not inherited.
  6. A default constructor is supplied by the compiler if no other constructors are provided.
  7. this() refers to a constructor of the same class. super() refers to a superclass constructor.
  8. Non-static inner classes may not have static members. Static inner classes may not have non-static members.
  9. Local inner classes may only access variables and parameters that are declared as final and assigned a value.
  10. Anonymous inner classes are unnamed inner classes that are declared and created at the same time.

Key terms and concepts

  1. Classification: The organization of information into hierarchical categories.
  2. Inheritance: The passing on of design information from a superclass to a subclass.
  3. Single inheritance: The inheritance of class members from a single parent.
  4. Multiple inheritance: The inheritance of class members from more than one parent.
  5. Encapsulation: A quality of classes with well-defined and controlled interfaces.
  6. Polymorphism: Having many forms.
  7. Dynamic binding: A program compilation and execution feature that allows programs to delay until Runtime decisions about the type of objects that they access.
  8. Abstract method: A method whose implementation is deferred to a subclass.
    A method declared abstract cannot also be declared to be private, static, final, native, strictfp, or synchronized .
  9. Member: An element of a class or interface, such as a field variable, method, or inner class. An element of a package, such as a class, interface, or subpackage.
  10. Subclass: A class that extends another class. All classes are a subclass of themselves.
  11. Superclass: A class that is extended by another class.
  12. Strict subclass: A subclass that is not the class itself.
  13. Direct superclass: The class that is identified in a class's extends clause. If a class is declared without an extends clause, then its direct superclass is java.lang.Object.
  14. Access modifier: A modifier that is used to limit access to a class, class member, or constructor.
  15. Nested class: A class that is declared as a member of another class or interface.
  16. Enclosing scope: The instance of an outer class in which an instance of an inner class is created
  17. Top-level class: A class that is not nested or a static inner class.
  18. Scope: The extent of the context of a definition.
  19. Local inner class: An inner class that is declared local to a block of code.

Anonymous Class - Quiz

Click the Quiz link below to check your understanding of Java classes, interfaces, and objects.
Anonymous Class - Quiz