成为一名优秀的软件设计师的第一步是要意识到仅工作代码是不够的。引入不必要的复杂性以更快地完成当前任务是不可接受的。最重要的是系统的长期结构。任何系统中的大多数代码都是通过扩展现有代码库编写的,因此,作为开发人员,最重要的工作就是促进这些将来的扩展。因此,尽管您的代码当然必须工作,但您不应将“工作代码”视为主要目标。您的主要目标必须是制作出出色的设计,并且这种设计也会起作用。这是战略计划。
战略性编程需要一种投资心态。您必须花费时间来改进系统的设计,而不是采取最快的方式来完成当前的项目。这些投资会在短期内让您放慢脚步,但从长远来看会加快您的速度,如 图 3.1 所示。
一些投资将是积极的。例如,值得花一些时间为每个新类找到一个简单的设计。而不是实施想到的第一个想法,请尝试几种替代设计并选择最简洁的设计。试想一下将来可能需要更改系统的几种方式,并确保设计容易。编写好的文档是主动投资的另一个例子。
其他投资将是被动的。无论您预先投入多少,设计决策中都不可避免地会出现错误。随着时间的流逝,这些错误将变得显而易见。发现设计问题时,不要只是忽略它或对其进行修补。花一些额外的时间来修复它。如果您进行战略性编程,则将不断对系统设计进行小幅改进。这与战术编程相反,在战术编程中,您不断增加一些复杂性,这些复杂性将来会引起问题。
The first step towards becoming a good software designer is to realize that working code isn’t enough. It’s not acceptable to introduce unnecessary complexities in order to finish your current task faster. The most important thing is the long-term structure of the system. Most of the code in any system is written by extending the existing code base, so your most important job as a developer is to facilitate those future extensions. Thus, you should not think of “working code” as your primary goal, though of course your code must work. Your primary goal must be to produce a great design, which also happens to work. This is strategic programming.
Strategic programming requires an investment mindset. Rather than taking the fastest path to finish your current project, you must invest time to improve the design of the system. These investments will slow you down a bit in the short term, but they will speed you up in the long term, as illustrated in Figure 3.1.
Some of the investments will be proactive. For example, it’s worth taking a little extra time to find a simple design for each new class; rather than implementing the first idea that comes to mind, try a couple of alternative designs and pick the cleanest one. Try to imagine a few ways in which the system might need to be changed in the future and make sure that will be easy with your design. Writing good documentation is another example of a proactive investment.
Other investments will be reactive. No matter how much you invest up front, there will inevitably be mistakes in your design decisions. Over time, these mistakes will become obvious. When you discover a design problem, don’t just ignore it or patch around it; take a little extra time to fix it. If you program strategically, you will continually make small improvements to the system design. This is the opposite of tactical programming, where you are continually adding small bits of complexity that cause problems in the future.