Stephens Rod

Beginning Software Engineering


Скачать книгу

specifying the software's purpose and features, an end user who will eventually spend time working with (and reporting bugs in) the finished application, a lead developer who keeps other programmers on track (and not playing too much Flow Free), or the guy who fetches donuts for the weekly meeting, you need to understand how all the pieces of the process fit together. A failure by any of these people (particularly the donut wallah) affects everyone else, so it's essential that everyone knows the warning signs that indicate the project may be veering toward disaster.

      This book is mainly intended for people with limited experience in software engineering. It doesn't expect you to have any previous experience with software development, project management, or programming. (I suspect most readers will have some experience with donuts, but that's not necessary, either.)

      Even if you have some familiarity with those topics, particularly programming, you may still find this book informative. If you've been focusing only on the pieces of a project assigned to you, you still need to learn about how the pieces interact to help guide the project toward success.

      For example, I had been working as a programmer for several years and even taken part in some fairly large development efforts before I took a good look at the development process as a whole. I knew other people were writing use cases and deployment plans, but my focus was on my piece of the project. It wasn't until later, when I started taking a higher-level role in projects that I actually started to see the entire process.

      This book does not explain how to program. It does explain some techniques programmers can use to produce code that is flexible enough to handle the inevitable change requests, easy to debug (at least your code will be), and easy to enhance and maintain in the future (more change requests), but they are described in general terms and don't require you to know how to program.

      If you don't work in a programming role, for example if you're an end user or a project manager, you'll hopefully find that material interesting even if you don't use it directly. You may also find some techniques surprisingly applicable to nonprogramming problems. For example, techniques for generating problem-solving approaches apply to all sorts of problems, not just programming decisions. (You can also ask developers, “Are you using assertions and gray-box testing methods before unit testing?” just to see if they understand what you're talking about. Basically, you're using gray-box testing to see if the developers know what gray-box testing is. You'll learn more about that in Chapter 8, “Testing.”)

      APPROACH

      This book is divided into two parts. The first part describes the basic tasks you need to complete and deliver useful software. Things such as design, programming, and testing. The book's second part describes some common software development models that use different techniques to perform those tasks.

      Before you can begin to work on a software development project, however, you need to do some preparation. You need to set up tools and techniques that help you track your progress throughout the project. Chapter 1, “Software Engineering from 20,000 Feet,” describes these “before-the-beginning” activities.

      After you have the preliminaries in place, there are many approaches you can take to produce software. All those approaches have the same goal (making useful software), so they must handle roughly the same tasks. These are things such as gathering requirements, building a plan, and actually writing the code. The first part of this book describes these tasks. Chapter 1 explains those tasks at a high level. Chapters 2 through 11 provide additional details about what these tasks are and how you can accomplish them effectively.

      The second part of the book describes some of the more popular software development approaches. All these models address the same issues described in the earlier chapters but in different ways. Some focus on predictability so that you know exactly what features will be provided and when. Others focus on creating the most features as quickly as possible, even if that means straying from the original design. Chapters 12 through 14 describe some of the most popular of these development models.

      That's the basic path this book gives you for learning software engineering. First learn the tasks you need to complete to deliver useful software. Then learn how different models handle those tasks.

      However, many people have trouble learning by slogging through a tedious enumeration of facts. (I certainly do!) To make the information a bit easier to absorb, this book includes a few other elements.

      Each chapter ends with exercises that you can use to see if you were paying attention while you read the chapter. I don't like exercises that merely ask you to repeat what is in the chapter. (Quick, what are some advantages and disadvantages of the ethereal nature of software?) Most of the exercises ask you to expand on the chapter's main ideas. Hopefully, they'll make you think about new ways to use what's explained in the chapter.

      Sometimes, the exercises are the only way I could sneak some more information into the chapter that didn't quite fit in any of its sections. In those cases, the questions and answers provided in Appendix A are like extended digressions and thought experiments than quiz questions.

      I strongly recommend that you at least skim the exercises and think about them. Then ask yourself if you understand the solutions. All the solutions are included in Appendix A, “Solutions to Exercises.”

      WHAT THIS BOOK COVERS (AND WHAT IT DOESN'T)

      This book describes software engineering, the tasks that you must perform to successfully complete a software project, and some of the most popular developer models you can use to try to achieve your goals. It doesn't cover every last detail, but it does explain the overall process so that you can figure out how you fit into the process.

      This book does not explain every possible development model. Actually, it barely scratches the surface of the dozens (possibly hundreds) of models that are in use in the software industry. This book describes only some of the most popular development approaches and then only relatively briefly.

      If you decide you want to learn more about a particular approach, you can turn to the hundreds of books and thousands of web pages written about specific models. Many development models also have their own organizations with websites dedicated to their promotion. For example, see www.extremeprogramming.org, agilemanifesto.org, and www.scrum.org.

      This book also isn't an exhaustive encyclopedia of software development tricks and tips. It describes some general ideas and concepts that make it easier to build robust software, but its focus is on higher-level software engineering issues, so it doesn't have room to cover all the clever techniques developers use to make programs better. This book also doesn't focus on a specific programming language, so it can't take advantage of language-specific tools or techniques.

      WHAT TOOLS DO YOU NEED?

      You don't need any tools to read this book. All you need is the ability to read the book. (And perhaps reading glasses. Or perhaps a text-to-speech tool if you have an electronic version that you want to “read.” Or perhaps a friend to read it to you. Okay, I guess you have several options.)

      To actually participate in a development effort, you may need a lot of tools. If you're working on a small, one-person project, you might need only a programming environment such as Visual Studio, Eclipse, RAD Studio, or whatever. For larger team efforts you'll also need tools for project management, documentation (word processors), change tracking, software revision tracking, and more. And, of course, you'll need other developers to help you. This book describes these tools, but you certainly don't need them to read the book.

      CONVENTIONS

      To help you get the most from the text and keep track of what's happening, I've used several conventions throughout the book.

      SPLENDID SIDEBARS

      Sidebars such as this one contain additional information and side topics.

      WARNING Boxes like this one hold important information that is directly relevant to the surrounding text. There are a lot of ways a software project