UML ( Unified Modeling Language)

The Unified Modeling Language is only a language. It is not a way of designing a system, but it is a way to model a system.

The main object of UML is to make the project understanding more crisp and clear. It is a global computer industry modeling language to communicate between software professional in a project.

UML help us to create documents, artifacts and also give visualization so that we can understand the complex software engineering process of a project.

Model Software

The most important reason we model software is to achieve a high level of quality from our finished product.

Three steps to creating a quality system

•  Analysis
•  Design
•  Implementation

I like to think that a successul project is the result of a lot of analysis, less design, and even less implementation, becasues it is true that if you have the exact opposite order, you will have a complete nightmare on your hands. A lot of implementation with little design and even less analysis usually results in a product that is first riddled with bugs, and then doesn’t have the functionality that users require.

You can create six possible scenarios when developing a system

1.   Your product does what the client expets, it has good design, with a small number of bugs

2.   You do not know what the client expects, the design emphasizes the wrong expectations, and the product is riddled with bugs

3.   You know most of what the client wants, but the desig does not support the need of the analysis and the product is riddled with bugs

4.   You know what the client needs, but your design does not implement it and your implementation is overcompensating to try to fix it

5.   You have no idea what the client wants, the design is overly complicated for the functionality you will provide, and your implementation is trying to overcompensate for the problems

6.   You have a good idea of what the client wants, the design is overly complicated for the needs analyzed, and the implementation is not solid enough

Three views of the project from UML perspective

There are 12 diagrams in UML they are divided into 3 main views as below

• Structure diagram
• Behavior diagram
• Model management diagram

Structure diagram

UML provide four types of structure diagram

1.   Class diagrams
2.   Object diagrams
3.   Component diagrams
4.   Deployment diagrams

Behavior diagram

UML  provide five types of Behavior diagram

1.   Use Case diagrams

2.   Sequence diagrams

3.   Activity diagrams

4.   Collaboration diagrams

5.   State chart diagrams

Model Management diagram

UML provide three types of Model management diagram

1.   Packages

2.   Subsystems

3.   Models