Software System Construction:Software implementation overview

By -

10.1 Introduction

The technical design has taken us to the stage where the design can be implemented into software. The three layers - business data, business objects, and presentation - will be preserved in the implementation. Strictly speaking, this chapter falls outside of the WISDM methods matrix, which addresses analysis and design as opposed to software construction. Many systems analysis and design texts stop at the construction phase, but this cut-off can be unsatisfactory because it fails to give a sense of closure to the analysis and design work. We will therefore demonstrate how the theatre booking system can be implemented as a working software system. We will call this software implementation of the theatre booking system design 'Ticket Manager'.

The construction of the Ticket Manager application requires three areas of technical expertise:

• Databases and Structured Query Language (SQL) (Microsoft Access 2000 for demonstration and Microsoft SQL Server 2000 for production operation) to implement the business data layer

• Web server-side programming (Macromedia ColdFusion) with the option of client-side JavaScript for added functionality and efficiency to implement the business logic layer

• Web authoring (Macromedia Dream Weaver and HTML) and graphics preparation (Macromedia Fireworks) to implement the user presentation layer.

Each of these topics deserves a complete text in its own right - and many are available in various degrees of thickness. In appendix C resources for these three aspects of web development are supplied and interested readers are encouraged to download evaluation copies of the software and to experiment for themselves. Furthermore, the database and complete source code for Ticket Manager can be downloaded from the WISDM site, www.wisdm.net, for installation on a local PC running the Microsoft Windows family of operating systems. One of the best ways to learn how to develop web applications is to look at the code of a working application, understand how it works, and then adapt (play with) the application. You will often learn more from looking at a well-designed Dream Weaver web site, such as the templates available from projectseven.com, than from any number of books on Dream Weaver and HTML, however exhaustive these texts might be.

10.2 Software implementation overview

The three-tier client-server architecture developed in the technical design is preserved in the implementation (figure 10.1).

Developing Web Information Systems-0106

The business data will be implemented in the live system with Microsoft SQL Server, but for the purposes of rapid prototyping and ease of software availability we will use Microsoft Access to illustrate the Ticket Manager application. Microsoft Access is intended as an end-user database; although it can cope with a small number of concurrent users (around 10), it is not recommended as an industrial-strength database server for the Internet. An upsizing wizard is supplied with Access to allow the database tables to be migrated to Microsoft SQL Server for use in a production environment. The business logic will be implemented as business objects using ColdFusion components, creating an insulating layer between the presentation layer and the business data. This introduces a degree of technical complexity that the developer new to ColdFusion would typically come across under one of the later 'advanced' chapters in a ColdFusion textbook. However, it is important to start with - and preserve - a three-tier architecture if the system is to be capable of being worked on by multiple developers concurrently and for the application to be maintainable and scalable in the future. The presentation layer will be developed using Dreamweaver. The graphical images will be prepared using Fireworks.

Comments

Post a Comment

Popular posts from this blog

The Conversion Cycle:The Traditional Manufacturing Environment

By -
Image
The Traditional Manufacturing Environment The conversion cycle consists of both physical and information activities related to manufacturing products for sale. The context-level data flow diagram (DFD) in Figure 7-1 illustrates the central role of the conversion cycle and its interactions with other business cycles. Production is triggered by customer orders from the revenue cycle and/or by sales forecasts from marketing. These inputs are used to set a production target and prepare a production plan, which drives production activities. Purchase requisitions for the raw materials needed to meet production objectives are sent to the purchases procedures (expenditure cycle), which prepares purchase orders for vendors. Labor used in production is transmitted to the payroll system (expenditure cycle) for payroll processing. Manufacturing costs associated with intermediate work-in-process and finished goods (FG) are sent to the general ledger (GL) and financial reporting system. Dependin
Read more

The Revenue Cycle:Manual Systems

By -
Image
Manual Systems The purpose of this section is to support the system concepts presented in the previous section with models depicting people, organizational units, and physical documents and files. This section should help you envision the segregation of duties and independent verifications, which are essential to effective internal control regardless of the technology in place. In addition, we highlight inefficiencies intrinsic to manual systems, which gave rise to modern systems using improved technologies. SALES ORDER PROCESSING The system flowchart in Figure 4-12 shows the procedures and the documents typical to a manual sales order system. In manual systems, maintaining physical files of source documents is critical to the audit trail. As we walk through the flowchart, notice that in each department, after completion of the assigned task, one or more documents are filed as evidence that the task was completed. Sales Department The sales process begins with a customer cont
Read more

HIPO (hierarchy plus input-process-output)

By -
Image
HIPO (hierarchy plus input-process-output) 64.1 Purpose The HIPO (Hierarchy plus Input-Process-Output) technique is a tool for planning and/or documenting a computer program. A HIPO model consists of a hierarchy chart that graphically represents the program’s control structure and a set of IPO (Input-Process-Output) charts that describe the inputs to, the outputs from, and the functions (or processes) performed by each module on the hierarchy chart. 64.2 Strengths, weaknesses, and limitations Using the HIPO technique, designers can evaluate and refine a program’s design, and correct flaws prior to implementation. Given the graphic nature of HIPO, users and managers can easily follow a program’s structure. The hierarchy chart serves as a useful planning and visualization document for managing the program development process. The IPO charts define for the programmer each module’s inputs, outputs, and algorithms. In theory, HIPO provides valuable long-term documentation. However
Read more