Programming: Classes

“A building contractor can understand a blueprint designed by an architect because both of them use the same set of rules and conventions. When you create a class, you’re the architect. The blueprint you must create must communicate your ideas to the computer” (Mueller 250). A class is a set of instructions used to describe the structure of the data. Through the book, I learned what classes are and some of the fundamentals of creating a class.

               First in programming, a class is written out as “class” followed by a title. For example, if I were to write out a program about books it would be written out like this.

                So far, I just created my class, but it is not doing anything. So, to make it do something, I can add a class constructor which basically creates an object in the class and it is written out like this.

                 Now that I have the constructor, I can add specific details that I want to include to the class. This would be called instance variables. For example, I could add a publish date to the book class. An instance variable would be shown as the “int” data type and it would be written out like this.

                 Now that I have the object and its specifics I can make it more detailed by adding parameters to the class constructor. Parameters uses data types with specific attributes. If, I was to input the date of the year of a book published, it would just output the year date but not say it is the publish date. To fix that, parameters are used, and it is written out like this.

                 To recap, a class is a blueprint of how the data are laid out. A constructor creates the object and an object stores the state of the class in the parenthesis. Lastly, a parameter helps the object be specified when given a value. There is more to creating a class, but this is what I have learned so far. What do you think is the most important things to remember when programming?

Mueller, John Paul. Java eLearning Kit For Dummies. Wiley, 2014.