Java™ Application Development on Linux - Dator

264Chapter 11Balancing Acts: An Imaginary ScenarioYou will also see the requirements for a simple budget application that willbe used in succeeding chapters. It has little to do with real budgets, but lots todo with a simple application that we can use to demonstrate various Javatechnologies.11.2STATEMENT OF THE NEEDFinancial planning is something that everyone does. The basic tool of financialplanning is the budget. But unlike the home budget, the budget of a large corporationis managed at multiple levels within the organization. Sure, at somelevel, the board, the CEO, and the CFO decide that “we will spend X milliondollars for operations for this quarter,” but that is the start of the process, notthe end.From there, the feeding frenzy of middle management begins. And keepingtrack of things becomes an important aspect of financial control and corporategovernance.Realistically, any large business will already have processes and tools inplace that meet this need. We are not expecting that what we develop here willbe anything that a business will actually adopt to manage this process. Rather,our goal is to illustrate some methods of software development that actuallywork to build real Java application. The outline of methods and code could beused to address many classes of enterprise software.11.3HOW TO DEVELOP SOFTWAREThere is a science of Software Engineering. The development of software canbe made an engineering discipline, with mathematical rules and metrics ofsuccess. Every aspect of a complete system can be worked out in detail beforehandso that you know, well before a line of code is written, what the outcomewill be.That’s not what we’re talking about here.We are talking about software development not as it happens at NASA,medical device companies, and in factories where nuclear missiles are made. Inthose contexts, the potential costs of error are extremely high, ranging from themultibillion dollar loss (and public embarrassment) of crashing a spacecraft intoMars, on through having heart pacemakers fire off incorrectly, right to endinglife as we know it on this planet. In such cases, no matter how much the correct