定义常量的几种方式与调用

 1 interface ColorConstant {
 2      /**
 3       * 红色
 4       */
 5      int RED = 1;  
 6       /**
 7        * 黄色
 8       */
 9      int YELLOW = 2;
10  }
11 调用方式：ColorConstant.RED

 1 enum ConstantEnum {    
 2     RED("红色", 1), YELLOW("黄色", 2)；
 3     private String name ;
 4     private int index ;  
 5     private Color( String name , int index ){
 6         this.name = name ;
 7         this.index = index ;
 8     }  
 9     public String getName() {
10         return name;
11     }
12     public void setName(String name) {
13         this.name = name;
14     }
15     public int getIndex() {
16         return index;
17     }
18     public void setIndex(int index) {
19         this.index = index;
20     }
21 }  
22 调用方式：ConstantEnum.RED.getName();
23 //遍历所有的枚举
24         for( ConstantEnum color : ConstantEnum .values()){
25             System.out.println( color + "  name: " + color.getName() + "  index: " + color.getIndex() );
26         }

1 class ColorConstant {    
2     public static final int RED = 1;    
3     public static final int YELLOW = 2;
4 }
5 调用方式：ColorConstant.RED；