java枚举类定义

知识点：

1.枚举的优雅创建
2.values()遍历枚举中的常量值
3.valueof(String name) ：根据名称获取枚举类中定义的常量值;要求字符串跟枚举的常量名必须一致;
4.枚举类中重写了toString()方法,返回的是枚举常量的名称;

下面是枚举创建：

package ***;
 
import com.baomidou.mybatisplus.core.enums.IEnum;
 
import java.io.Serializable;
 
public enum ReturnTypeEnum implements IEnum {
 
    SUCCESS("S","成功"),
    ERROR("E","失败"),
    WARNING("W","警告");
 
    private String id;
    private String desc;
 
    ReturnTypeEnum(String id, String desc) {
        this.id = id;
        this.desc = desc;
    }
 
    public String getId() {
        return id;
    }
 
    public void setId(String id) {
        this.id = id;
    }
 
    public String getDesc() {
        return desc;
    }
 
    public void setDesc(String desc) {
        this.desc = desc;
    }
 
    public static ReturnTypeEnum getValue(String id) {
        for (ReturnTypeEnum returnTypeEnum:values()){
            if (returnTypeEnum.getId().equals(id)){
                return returnTypeEnum;
            }
        }
        return null;
    }
 
    @Override
    public Serializable getValue() {
        return null;
    }
    public static void main(String[] args) {
       //测试values()是否遍历
        System.out.println(ReturnTypeEnum.SUCCESS.getValue("S"));
	//测试toString()
        System.out.println(ReturnTypeEnum.SUCCESS.getValue("S").toString());
	//测试valueof().
        System.out.println(ReturnTypeEnum.valueOf("SUCCESS").getId());
    }