资源包包含特定于语言环境的对象。当程序需要一个特定于语言环境的资源时（如String），程序可以从适合当前用户语言环境的资源包中加载它。使用这种方式，可以编 写很大程度上独立于用户语言环境的程序代码，它将资源包中大部分（即便不是全部）特定于语言环境的信息隔离开来。这使编写的程序可以：轻松地本地化或翻译成不同的语言 一次处理多个语言环境以后可以轻松进行修改，以便支持更多的语言环境

RBPropDemo.java

import java.util.Locale;  import java.util.ResourceBundle;  import java.util.Set;    public class RBPropDemo {    public static void main(String[] args) {      ResourceBundle.clearCache();      String bundleName = "myproj.MyResources";        ResourceBundle myResources = ResourceBundle.getBundle(bundleName, Locale.GERMAN);        System.out.println("Key's values:");      System.out.println(myResources.getString("okKey"));      System.out.println(myResources.getString("cancelKey"));      System.out.println(myResources.getString("submitKey"));      System.out.println("\nChecking okKey in resource bundle:");      if (myResources.containsKey("okKey")) {        System.out.println("okKey exists! " + " Value = " + myResources.getString("okKey"));      } else {        System.out.println("The key Doesn't Exist");      }        System.out.println("\nGet a set of keys:");      Set<String> keySet = myResources.keySet();      Object[] keys = keySet.toArray();      for (int i = 0; i < keys.length; i++) {        System.out.println("Key " + (i + 1) + " = " + keys[i]);      }    }  }    /*  MyResources.properties file    okKey = OK  cancelKey = Cancel  submitKey = Submit    The MyResources_de.properties file  cancelKey = Abbrechen  */