On the reusability of software design

Posted on 2009-07-06 filed under: Development (RSS) 46 views

On the reusability of software design

[Note]

This is my systems analyst operating practice exam papers, I will try to ensure the authenticity of all cases, but it is inevitable that fictional Please慎入.

[Abstract]

In May 2008 to April 2009, I participated in a provincial web-based wireless carrier operating the Office of the development of three projects, and served as manager of software development jobs. Online business hall of the provincial radio operator's online portal, is its e-marketing channels an important part. In this paper, the project team experience to online business with the Office of Communications BOSS machine interface design and development as an example, we detail how to design reusability. In the design process, we adopted a cross-platform, high reusability of the WebService technology. Focused on the reuse project WebService to bring many advantages. It also discussed the visit to efficiency, safety and services, such as in terms of defects, as well as response measures. The final design from the reusability point of view, put forward for the future of the wireless operators BOSS system design and operation of the Prospect.

[Body]

In May 2008 to April 2009, I participated in a provincial operator of wireless Internet banking hall three projects, in this project, I served as a software development manager role. My main task is to participate in analysis of customer demand, the Office of the online business analysis and 3 for system design.

Online business is the Office of the provincial operators online portals, e-marketing channels is an important part. Its main features include: corporate image promotion; of new business, new promotional activities; customers and other business inquiries and processing. Electronic channels with customers to enhance awareness of, the original 2-line business in the Office of hardware, has been unable to meet the growing number of customers. In software architecture has been unable to respond quickly to frequent changes to complex needs. Therefore, the proposed operator for the line item 3 hall of our building projects. The construction of three targets as follows: Office of the online registration of business customers from 2,000,000 to 5,000,000, and from the hardware, software and other areas to ensure that customers use.

Composition of the project include: a project manager, a software development manager, a system manager, three programmers, two page production, a total of two systems 10. Project development platform for J2EE.

The project for the general situation in hardware: 14 IBM BCH, install apache, a web front-end server. 6 IBM P52A, install weblogic, as the application server. 2 P570 as authentication server. 2 P570, install oracle, as the database server. Operating system using the Red Hat Enterprise linux 5, as well as AIX5.3.

At present, the Office of Internet business through the end of three successful inspection and on-line and on time. In the beginning of the end of the business for the peak period, customers can guarantee the normal visit. This project has been the provincial wireless carriers and the leadership of my company recognition.

With the development of software industry, software reuse technology is receiving increasing attention. Since the reusable software elements are time-tested, accurate and effective software unit, so the past through the repeated use of the software elements that can reduce development risk, to save development costs and improve development efficiency and software quality improved significantly. Reusable element of a wide range of software, including the demand for reuse, design reuse, document reuse, reusable code and so on. Reuse of these different size dispersed in the software at different stages of the life cycle. I will combine online banking hall of the three design and development work, specifically to discuss how I am a software design reusability.

The wireless carrier customers to carry out some 40 operations, such as: customer identification authentication, single detailed inquiries, billing inquiries, balance inquiries, integral inquiry, application and cancellation of short message, the shutdown and so on. Online banking hall itself does not deal with the request of customers, but the request will be forwarded to clients of the wireless operator's Business Operation Support System, hereinafter referred to as BOSS system. BOSS Office for the online business to provide a machine interface, and provides online banking hall and the communication protocol. Office of the needs of online business in accordance with the requirements of BOSS, the communication with the BOSS. BOSS Business Office to the Web interface is the way to communicate through the socket, and the need for line of business by the Office of the maintenance of a message queue. BOSS the message queue and the establishment of a number of long connections, and always maintain communication with the BOSS. Message queue in the store the customer's request, and then through the scheduling process, each client request sent to the BOSS processed, BOSS into the results returned to the line of business to respond to the Office of the queue, and then respond to the results of the final return to the customer. It can be seen that in accordance with the demands of message queue BOSS is very challenging. First, it should be able to deal with a higher efficiency of large-scale customer requests, followed by it must have a high reliability and fault tolerance.

"Internet banking hall 3" is actually a larger scope of the concept, which includes online banking hall, business hall handheld, mobile city, unified authentication platform, such as sub-project. These subprojects are to communicate the needs and BOSS. BOSS as a result of communication and interface program with a greater complexity, and it should not have to allow each subsystem to achieve the interface program. This requires the need to design a set of feasible options, so that each subsystem can reuse the interface program.

After several rounds of analysis and discussion, we have finally identified the use of WebService approach to the publication of the interface program. First of all, the development of senior staff to complete the development of interface program, and then through a standard interface program for each of the WSDL file to publish sub-project. This program has the following advantages.

First, it is the interface design and development process focused to a point. This group will be able to project a unified high-quality resources on the deployment of mission-critical, making more rational use of resources. It is also consistent with the purposes of the DRY principle, namely, the development not to repeat the same elements of the software. Software reuse it is also an important foundation.

Second, it allows for the online business BOSS Office of transparency in all subsystems, the interfaces hide the complexity of the procedure. For subsystems, they do not need any interface program concerned with the details of the work, only in accordance with the WSDL file to generate WebService call to the API. When customers request sent from the front, just like the various subsystems of the API calls as local calls to WebService.

Third, to maximize the reuse of the interface on the machine process. Through the use of WebService, online banking hall built in fact a narrow platform. In this platform to provide a more fine-grained services. Each subsystem can be a combination of these services and the call to complete a wide range of complex business. For example, the Office of Internet business integral dollar business. First, authentication of clients, brands and customers and then determine whether to allow the location of Exchange City, followed by customer to determine whether sufficient points, the final points deduction customers. If the handheld business to carry out the Office of points to exchange business, as long as the WAP site in accordance with the characteristics of the interface to change the front display and the same process to call the service platform to the service with no re-development.

Office System online business services platform is a WebService interface design and development of various subsystems of the basis of protection. Interface platform through the reuse of services, strong to save valuable development resources, reducing development risk, saving development time. Despite the many benefits and advantages, as we experience the lack of design and development process have encountered a lot of problems.

First, WebService access efficiency. As a result of the application and the interface between the intervention and a middle layer, making the visit to the efficiency of applications has declined. WebService Client and server side need to be SOAP packet assembly and disassembly operation, the final results would also like to put into operation in response to the physical object, it will affect the overall operating efficiency.

During his visit to the efficiency, we minimize the WebService object structure for the analysis and assembly operation, makes the structure of the specific business objects for the WebService transparency. For example, detailed data in a single transfer process, always maintain a long string, to resolve it on the application server to operate, even on the client.

Second, the security issues. Initially, the Internet operating system are the Office of the project by our company to develop and complete, so in safety and does not require too much attention. However, due to the Office of the late business online business expansion, and some systems from other manufacturers will need to cooperate with us to complete. At this point, we must fully open their service platform WebService. Mobile operator customer information is very sensitive information, such opening up has greatly increased the security risks.

In order to ensure the safe use of the service platform, we have stepped up logging work, making any calls are well documented. And other manufacturers and strict security agreement was signed, both from a technical and institutional aspects as far as possible to ensure security. Of course, we believe that these measures are far from adequate, we will in future work, further study of practical security measures.

Third, affairs. Office of the subsystem-line business to complete a business often requires a number of service calls to complete, such as the above mentioned points in dollar business. If a business needs to complete the service call several times, then an error when the last step, it is difficult to roll back to initial state.

To address this issue, we are sensitive to the special design of the larger particle size business services, which to some extent alleviated the affairs. For some of the services is really difficult to solve problems, we have adopted the way of human intervention to make up for deficiencies in the system. For example, when an operational error in the implementation process will be manual system maintenance staff to check customer status, and restore client state.

Finally, from a wider perspective, the Office of the item out of online business, as well as ringtones, MMS, Office business entities, self-service terminals, such as a large number of external systems and BOSS system is closely linked. BOSS system should put all the services are standard, loosely coupled and can be released by the form of collaboration, thus avoiding the major electronic channels must machine interface to realize their own problems. Reuse of this large particle size will go a long way to save the operator's operating costs, as well as the new system to pave the way for the development and construction.