5: OO ConceptsHomepage  « Java5 Certification « 5: OO Concepts

We start this section by looking at encapsulation, its advantages and how to achieve it within our code. We then look at the design principles of coupling and cohesion and describe the benefits of loose coupling and high cohesion. We then explain polymorphism and how we use it in the Java language before looking at object reference casting and determine when casting will be necessary whilst recognizing compiler vs. runtime errors, related to it. After this we examine the effect of modifiers on inheritance with respect to constructors, instance or static variables, and instance or static methods. We then look at code that declares and/or invokes overridden or overloaded methods and code that declares and/or invokes superclass or overloaded constructors. We finish the section by investigating code that implements "is-a" and/or "has-a" relationships.

Lets take a look at the points outlined at the Oracle Website for this part of the certification.

  • Section 5: OO Concepts

    1. Develop code that implements tight encapsulation, loose coupling, and high cohesion in classes, and describe the benefits.

    2. Given a scenario, develop code that demonstrates the use of polymorphism. Further, determine when casting will be necessary and recognize compiler vs. runtime errors related to object reference casting.

    3. Explain the effect of modifiers on inheritance with respect to constructors, instance or static variables, and instance or static methods.

    4. Given a scenario, develop code that declares and/or invokes overridden or overloaded methods and code that declares and/or invokes superclass or overloaded constructors.

    5. Develop code that implements "is-a" and/or "has-a" relationships.

5.1 Encapsulation, Coupling, Cohesion

In our first lesson within this section we look at encapsulation, its advantages and how to achieve it within our code. We then look at the design principles of coupling and cohesion and describe the benefits of loose coupling and high cohesion.

5.2 Polymorphism & Casting

In this lesson we explain polymorphism and how we use it in the Java language before looking at object reference casting and determine when casting will be necessary whilst recognizing compiler vs. runtime errors, related to it.

5.3 Modifiers & Inheritance

In this lesson we examine the effect of modifiers on inheritance with respect to constructors, instance or static variables, and instance or static methods.

5.4 Constructors & Instantiation

In this lesson we look at code that declares and/or invokes overridden or overloaded methods and code that declares and/or invokes superclass or overloaded constructors.

5.5 IS-A & HAS-A Relationships

In our final lesson within this section we investigate code that implements "is-a" and/or "has-a" relationships.


Related Java5 Tutorials

OO Concepts - Encapsulation
OO Concepts - Polymorphism
OO Concepts - Overriding Methods
Objects & Classes - Overloaded Methods
OO Concepts - Accessing Superclass Members
OO Concepts - Superclass Constructors
OO Concepts - Static Overrides?
OO Concepts - IS-A and HAS-A Relationships


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