Software Engineering

The new edition of Software Engineering presents a step-by-step  methodology that integrates Modeling and Design, UML, Patterns,  Test-Driven Development, Quality Assurance, Configuration Management,  and Agile Principles throughout the life cycle. The overall approach is  casual and easy to follow, with many practical examples that show the  theory at work. The author uses his experiences as well as real-world  stories to help the reader understand software design principles,  patterns, and other software engineering concepts. The book also  provides stimulating exercises that go far beyond the type of question  that can be answered by simply copying portions of the text.

Many  people do not know the scope and usefulness of software engineering,  and the discipline is often misunderstood. Many media outlets deem  software engineering as writing Java programs. Some students think that  software engineering includes everything related to software. Others  think that software engineering is drawing UML diagrams, as the  following story illustrates. Years ago, after the first class of a  software engineering course, a student told me, “professor, you know  that this will be an easy course for me because we’ve drawn lots of UML  diagrams before.” At the end of the semester, the student came to me  again and said, “professor, I want to tell you that we worked very hard,  but we learned a lot about OO design. It is not just drawing UML  diagrams.” So what is software engineering? As a discipline, it  encompasses research, education, and application of engineering  processes, methodologies, quality assurance, and project management to  significantly increase software productivity and software quality while  reducing software cost and time to market. A software process describes  the phases and what should be done in each phase. It does not specify  (in detail) how to perform the activities in each phase. A modeling  language, such as UML, defines the notations, syntax, and semantics for  communicating and documenting analysis and design ideas. UML and the  Unified Process (UP) are good and necessary but not sufficient. This is  because how to produce the analysis and design ideas required to draw  meaningful UML diagrams is missing.

To fill the gap mentioned  above, we need a methodology or a “cook-book.” Unlike a process, a  methodology is a detailed description of the steps and procedures or how  to carry out the activities to the extent that a beginner can follow to  produce and deploy the desired software system. Without a methodology, a  beginning software engineer would have to spend years of on-the-job  training to learn design, implementation, and testing skills.

This  book is also motivated by emerging interests in Agile processes, design  patterns, and test-driven development (TDD). Agile processes emphasize  teamwork, design for change, rapid deployment of small increments of the  software system, and joint development with the customer and users.  Design patterns are effective design solutions to common design  problems. They promote software reuse and improve team communication.  Patterns also empower less-experienced software engineers to produce  high-quality software because patterns encode software design  principles. TDD advocates testable software, and requires test scripts  to be produced before the implementation so that the latter can be  tested immediately and frequently.