1 /** 
  2  * Method One 
  3  */  
  4 interface ConstantInterface {  
  5     String SUNDAY = "SUNDAY";  
  6     String MONDAY = "MONDAY";  
  7     String TUESDAY = "TUESDAY";  
  8     String WEDNESDAY = "WEDNESDAY";  
  9     String THURSDAY = "THURSDAY";  
 10     String FRIDAY = "FRIDAY";  
 11     String SATURDAY = "SATURDAY";  
 12 }  
 13 /** 
 14  * Method Two  
 15  */  
 16 enum ConstantEnum {  
 17     SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY  
 18 }  
 19 /** 
 20  * Method Three 
 21  */  
 22 class ConstantClassField {  
 23     public static final String SUNDAY = "SUNDAY";  
 24     public static final String MONDAY = "MONDAY";  
 25     public static final String TUESDAY = "TUESDAY";  
 26     public static final String WEDNESDAY = "WEDNESDAY";  
 27     public static final String THURSDAY = "THURSDAY";  
 28     public static final String FRIDAY = "FRIDAY";  
 29     public static final String SATURDAY = "SATURDAY";  
 30 }  
 31 /** 
 32  * Method Four 
 33  * http://www.ibm.com/developerworks/cn/java/l-java-interface/index.html 
 34  */  
 35 class ConstantClassFunction {  
 36     private static final String SUNDAY = "SUNDAY";  
 37     private static final String MONDAY = "MONDAY";  
 38     private static final String TUESDAY = "TUESDAY";  
 39     private static final String WEDNESDAY = "WEDNESDAY";  
 40     private static final String THURSDAY = "THURSDAY";  
 41     private static final String FRIDAY = "FRIDAY";  
 42     private static final String SATURDAY = "SATURDAY";  
 43     public static String getSunday() {  
 44         return SUNDAY;  
 45     }  
 46     public static String getMonday() {  
 47         return MONDAY;  
 48     }  
 49     public static String getTuesday() {  
 50         return TUESDAY;  
 51     }  
 52     public static String getWednesday() {  
 53         return WEDNESDAY;  
 54     }  
 55     public static String getThursday() {  
 56         return THURSDAY;  
 57     }  
 58     public static String getFirday() {  
 59         return FRIDAY;  
 60     }  
 61     public static String getSaturday() {  
 62         return SATURDAY;  
 63     }  
 64 }  
 65 public class TestConstant {  
 66     static final String day = "saturday";  
 67     public static void main(String[] args) {  
 68         System.out.println("Is today Saturday?");  
 69         System.out.println(day.equalsIgnoreCase(ConstantInterface.SATURDAY));  
 70         System.out.println(day.equalsIgnoreCase(ConstantEnum.SATURDAY.name()));  
 71         System.out.println(day.equalsIgnoreCase(ConstantClassField.SATURDAY));  
 72         System.out.println(day.equalsIgnoreCase(ConstantClassFunction  
 73                 .getSaturday()));  
 74     }  
 75 }  
 76 [java] view plain copy print?
 77 /** 
 78  * Method One 
 79  */  
 80 interface ConstantInterface {  
 81     String SUNDAY = "SUNDAY";  
 82     String MONDAY = "MONDAY";  
 83     String TUESDAY = "TUESDAY";  
 84     String WEDNESDAY = "WEDNESDAY";  
 85     String THURSDAY = "THURSDAY";  
 86     String FRIDAY = "FRIDAY";  
 87     String SATURDAY = "SATURDAY";  
 88 }  
 89 /** 
 90  * Method Two  
 91  */  
 92 enum ConstantEnum {  
 93     SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, FRIDAY, SATURDAY  
 94 }  
 95 /** 
 96  * Method Three 
 97  */  
 98 class ConstantClassField {  
 99     public static final String SUNDAY = "SUNDAY";  
100     public static final String MONDAY = "MONDAY";  
101     public static final String TUESDAY = "TUESDAY";  
102     public static final String WEDNESDAY = "WEDNESDAY";  
103     public static final String THURSDAY = "THURSDAY";  
104     public static final String FRIDAY = "FRIDAY";  
105     public static final String SATURDAY = "SATURDAY";  
106 }  
107 /** 
108  * Method Four 
109  * http://www.ibm.com/developerworks/cn/java/l-java-interface/index.html 
110  */  
111 class ConstantClassFunction {  
112     private static final String SUNDAY = "SUNDAY";  
113     private static final String MONDAY = "MONDAY";  
114     private static final String TUESDAY = "TUESDAY";  
115     private static final String WEDNESDAY = "WEDNESDAY";  
116     private static final String THURSDAY = "THURSDAY";  
117     private static final String FRIDAY = "FRIDAY";  
118     private static final String SATURDAY = "SATURDAY";  
119     public static String getSunday() {  
120         return SUNDAY;  
121     }  
122     public static String getMonday() {  
123         return MONDAY;  
124     }  
125     public static String getTuesday() {  
126         return TUESDAY;  
127     }  
128     public static String getWednesday() {  
129         return WEDNESDAY;  
130     }  
131     public static String getThursday() {  
132         return THURSDAY;  
133     }  
134     public static String getFirday() {  
135         return FRIDAY;  
136     }  
137     public static String getSaturday() {  
138         return SATURDAY;  
139     }  
140 }  
141 public class TestConstant {  
142     static final String day = "saturday";  
143     public static void main(String[] args) {  
144         System.out.println("Is today Saturday?");  
145         System.out.println(day.equalsIgnoreCase(ConstantInterface.SATURDAY));  
146         System.out.println(day.equalsIgnoreCase(ConstantEnum.SATURDAY.name()));  
147         System.out.println(day.equalsIgnoreCase(ConstantClassField.SATURDAY));  
148         System.out.println(day.equalsIgnoreCase(ConstantClassFunction  
149                 .getSaturday()));  
150     }  
151 }