Java 常量文件

Java constants file(Java 常量文件)

本文介绍了Java 常量文件的处理方法,对大家解决问题具有一定的参考价值,需要的朋友们下面随着小编来一起学习吧!

问题描述

I'm developing an Android application and I'm very new on Java and Android.

I want to create some constants to use in some activities. Where can I define these constants?

Thanks.

解决方案

It's considered bad practice in java, and most OO languages, to define a class simply to hold constants. It's much better to define the constants in a class they are associated with. Usually there is one. e.g.

interface MyComponent {
  /** The default height for a component */
  public static final int DEFAULT_HEIGHT = 5;
  // other stuff
}

If there really isn't one feel free to define a separate class.

EDIT:The key things here are:

  1. Make the constants easy to find. If there is a 'natural' place to put them, put them there (i.e. the default height for Component objects belong in the Component class).
  2. Don't have higher coupling than you need to. Putting all your constants in one 'Constants' class makes for high coupling, especially as subsequent modifiers tend to then put ALL constants in the Constants class, whether or not there is another class they could naturally be put in.
  3. Just because a constant is used by more than one class that doesn't mean it should be in a 'Constants' class. If a constant is used by 'Application' and classes that use the Application class then put it in the Application class. That way you are not increasing the coupling.

这篇关于Java 常量文件的文章就介绍到这了,希望我们推荐的答案对大家有所帮助,也希望大家多多支持编程学习网!

本文标题为:Java 常量文件

基础教程推荐