Once you get the hang of a programming language, writing code to do what you want is actually pretty easy. What's hard is writing code that's easy to adapt when your requirements change. Rarely do we have the luxury of a perfect feature set before we've fired up our editor.
当你掌握了一门编程语言，你会发现写代码来实现某个你想要实现的功能是件相当容易的事情。难的是写出在此基础上容易添加或更改功能的代码，因为我们几乎没有可能不更改程序的功能或者特性。
A powerful tool we have for making change easier is decoupling. When we say two pieces of code are "decoupled", we mean a change in one usually doesn't require a change in the other. When you change some feature in your game, the fewer places in code you have to touch, the easier it is.
Components decouple different domains in your game from each other within a single entity that has aspects of all of them. Event Queues decouple two objects communicating with each other, both statically and in time. Service Locators let code access a facility without being bound to the code that provides it.
组件将游戏的不同方面互相分离开却仍然具备它们的特性。[事件队列](05.2-Event Queue.md)能够静态而且及时的将两个对象通信分离开。[服务定位器](05.3-Service Locator.md)让代码能够访问到设备却不需要被绑定到提供服务的代码上。
- 组件
- [事件队列](05.2-Event Queue.md)
- [服务定位器](05.3-Service Locator.md)