OO System analyst Path-use Case Analysis Series (5)--users, business use cases, and business scenarios

Long time no pen, during this period thanks to many friends like and encouragement, do not write something will be sorry for these friends.

What do you write? In the original scenario, you should start writing about how to translate from a business use case to a conceptual use case and a system use case, but to be honest, this step requires a majority of experience, and it's hard to find a universal step. Let's put it aside for a while, and it will be written in the future. The previous article about use case analysis of the general steps and methods, but also gave an example, but did not do a further explanation, so this one, the author decided to wordy before the content, said the business modeling the use of various diagrams, and their contribution to the needs.

Before you illustrate the example, repeat the requirements and remind the reader to download the instance, and only a few of the examples below will be selected to illustrate that the reader will be better able to understand the case. Well, let's look at the needs first, the librarian said:

We were originally a traditional library, the traditional way of borrowing requires readers to come to the library in person, which is very inconvenient, and with the increase of books and readership, especially, and a large number of readers to the library, so that the library is not enough space, staff. So think of the use of the network, so that readers through the network to borrow/return, so you can save a lot of site maintenance and staff costs, while the computer can easily retrieve the directory, so that the reader can borrow the book to need. In order to send the book to the borrower, we have contacted a speedpost company and B City Logistics company, and initially reached an agreement to send and retrieve the books between the borrower and the library. Readers on the internet to show and verify the library card, find the books they need, submit applications, the librarian confirmed, will inform the logistics company to fetch books, when readers get the book, logistics companies need to take the reader's signature back to prove that the reader has got the book. Of course, the reader is required to pay for the process. Returning a book is basically the same process.

Do you remember what you said on the last article? The first step is to identify users from the stakeholders. and define the relationships between these users. Users here refer to those stakeholders who will have a relationship with the system to be built. indicated by the following figure. This picture shows all the users and the relationships between them. It should be explained that the users here refer to the business user, not the "role" in the future system, although they may be in the future. The significance of this diagram is that it is clear that the future of the system is for who in the service, what they are doing, what characteristics, what is the relationship. This is the most basic starting point for use-case methods. Use cases, is people-oriented.

The second step is to find out what each user is going to do, the business use case. The business use case comes from the system analyst's interview with all the users in the previous step, summarizing and summarizing (I am considering writing an article on the research techniques of the system analyst, describing the interview techniques and Inductive methods). The author proposes to draw a business use case diagram from each user's perspective and from the perspective of each business, as follows:

User perspective: