Enum的使用

在项目开发中经常会使用到枚举，下面将举个例子，展示枚举的使用，不说废话，直接上代码。

 1 package com.tom.enumTest;
 2 
 3 public enum StatusType {
 4    A("FOOD","1"), B("CAR","2"), C("HOME","3");
 5    private String label;
 6    private String value;
 7 /**
 8  * @return the label
 9  */
10 public String getLabel() {
11     return label;
12 }
13 /**
14  * @param label the label to set
15  */
16 public void setLabel(String label) {
17     this.label = label;
18 }
19 /**
20  * @return the value
21  */
22 public String getValue() {
23     return value;
24 }
25 /**
26  * @param value the value to set
27  */
28 public void setValue(String value) {
29     this.value = value;
30 }
31 private StatusType(String label, String value) {
32     this.label = label;
33     this.value = value;
34 }
35   public StatusType getStatusTypeByValue(String val) {
36         for (StatusType statusType : StatusType.values()) {
37             if (statusType.getValue().equals(val)) {
38                 return statusType;
39             }
40         }
41       return null;
42   }
43   
44 }

View Code

 1 package com.tom.enumTest;
 2 
 3 import java.lang.reflect.Method;
 4 import java.util.ArrayList;
 5 import java.util.Arrays;
 6 import java.util.List;
 7 
 8 public class TestForEnum {
 9     private static final String GET_LABEL_METHOD = "getLabel";
10     public static <T extends Enum<T>> T translateByCode(final Class<T> clazz, final String code) {
11         if(code != null){
12             try {
13                 final Method m = clazz.getDeclaredMethod(GET_LABEL_METHOD);
14                 for (T t : inspectConstants(clazz)) {
15                     if (code.equals(m.invoke(t))) {
16                         return t;
17                     }
18                 }
19             } catch (Exception e) {            
20                 throw new RuntimeException(e);
21             }
22         }
23         return null;
24     }
25     public static <T extends Enum<T>> List<T> inspectConstants(final Class<T> clazz) {
26         return new ArrayList<T>(Arrays.asList(clazz.getEnumConstants()));
27     }
28     public static void main(String[] args) {
29         StatusType statusType = translateByCode(StatusType.class, "FOOD");
30         System.out.println(statusType.getLabel()+","+statusType.getValue());
31     }
32 }

View Code

public enum NumberEnum {
    ONE("1","哈哈"),
    TWO("2","嘿嘿"),
    THREE("3","呵呵");
    private String key;
    private String value;
    NumberEnum(String key,String value) {
        this.key = key;
        this.value = value;
    }

    public String getKey() {
        return key;
    }

    public String getValue() {
        return value;
    }
    public static NumberEnum getByKey(String key){
        NumberEnum[] numEnum = NumberEnum.values();
        for(NumberEnum dEnum : numEnum){
            if(redEnum.getValue() == key){
                return dEnum;
            }
        }
        return null;
    }

@Test
public void getIt4() {
   Map<String,Object> map = new HashMap<String, Object>();
   NumberEnum[] numEnum = NumberEnum.values();
   if ( null != numEnum && numEnum.length >=0) {
      for (NumberEnum nEnum : numEnum) {
         map.put(nEnum.getKey(),nEnum.getValue());

      }
   }
   System.out.println(map.size());
}