CLASS DIAGRAM

(Henderi, 2008)

Class Diagram is a diagram that shows the existing classes of a system and is associated with logic. Class diagrams describe the static structure of a system. Because the class diagram is the basis of almost all the power of object-oriented method including UML. 

(Jeffrey L. Whitten et al 2004:432) 

Class diagram is a graphic picture of a static object structure of a system, showing object classes that make up a system and also the relationship between object classes.

Class diagram is used to show some class and package diagrams that exist in the system or software that we use. Class diagram gives us a picture (static diagram) of the system or software and the relationship that is in it.

Elements-elements relevant in modeling UML class diagram consists of :

• Classes
• Class structure
• Class behavior
• Association
• Aggregation
• Dependency
• Derivatives relations
• Diversity and navigation indicators
• Role / Task name

Class diagram symbols :

• Class

Class is a block - a block object. A class-oriented programming is described as a box that is divided into 3 sections. The upper part is a part of the class name. Defines the center of the property or attribute class. The final section defines the method of the class.

• Association

An association relationship between two classes of the most common and is represented by a line connecting the two classes. This line can represent this kind of relationship and it can also display the number of dependency in a relationship. (Example: One-to-one, one-to-many, many-to-many).

In my post this time I will give you some ideas on how to use the class diagram in the depiction of the use of blogs. On previous occasions I have explained about the depiction usecase diagram with the theme of the blog system, here I developed this analogy by using a class diagram.

example :

In the class diagram is formed, there is a class 5 object. As for the class that is formed is manage profile, manage posts, manage comments, manage templates, and moneytize blog.

Each class has a method that can be used to communicate in the implementation phase. As for the methods that are owned respectively - each class as follows:

• Manage Profile (add_profile, edit_profile)

id_profile, nama_profile, email, set_idprofile, set_namaadmin, get_namaadmin

• Manage Post (add_post, edit_post, delete_post, view_post)

isi_post, tgl_post, panjang_isipost, set_isipost, get_isipost, set_tglpost, get_tglpost

• Manage Template Blog (edit, cadangkan, pulihkan)

isi_html, set_isihtml, get_isihtml

• Manage Comment (addcomment, viewcomment)

isi_comment, tgl_comment, panjang_isicomment, emal, set_isicomment, get_isicomment, set_tglcomment, get_tglcomment

• Moneytize Blog (approveiklan)

id_iklan, email, isi_iklan, tgl_iklan, get_idiklan, set_isiiklan, get_isiiklan, set_tgliklan, get_tgliklan

USECASE DIAGRAM

Use case is the circuit or description of a group of inter-related and form a system of regularly conducted or supervised by an actor. Use case are used to establish behavior of objects or things in a model and in realized by a collaboration. General use case is described by an ellipse with a solid line, usually containing of name .Use case describes the process of the system (system requirements from the user perspective).

In general use case is :

• Patterns of system behavior
• Sequence of related transactions performed by an actor

Use case diagram consists of :

• Use case
• Actors
• Relationship
• System boundary boxes (optional)
• Packages (optional)

Here is how to draw a use-case diagram:

Note:

Before making use-case diagram, you should start by making FDD first. This is just to help identify the processes in the system.

1. Start by registering actor associated with the Use-case, both the sender and receiver.
2. The components in a use-case diagram is a Use-Case Name, Description Use-case and participating actors and roles.
3.  Find demonstrating dependency semantic relations between two Use-case. If the Use-case "A" change can result in Use-case "B" will change as well.

There are 2 kinds of dependencies that need to be considered which include and extend

The following is an illustrative tool for use case diagram :

I will give an example of use case diagram blog creation.

The Explanation :

Before posting a blog, a user must log in to post a blog address with email id and its password. If the password does not match with email, the blog will give you a warning about password or email is incorrect. Once logged in, the administrator can perform several activities such as the following :

• Manage Profile

On this page, you can make additions profile and you can also edit profiles.

• Manage Post

You can add a post to edit the post and then you can do a review post on the blog page.

• Manage Template

On this page, you can explore your creativity to change the html of your blog template or download the template as you wish.

• Manage Comment

Users and visitors can further create comments for each blog post is posted by users, but before visitors will add a comment in a blog post, they must first log in with their email.

• Moneytize Blog

Visitors can leave request for posting ads on your blog, but first must get approval from the blog admin and the blog owner will usually get money from these ads.