自定义常量注解@Desc

以你之姓@ 2022-10-09 14:24 196阅读 0赞

package com.zyq.annotation;
    
    import java.lang.annotation.ElementType;
    import java.lang.annotation.Retention;
    import java.lang.annotation.RetentionPolicy;
    import java.lang.annotation.Target;
    
    /**
     * 通用配置注解
     */
    @Target(ElementType.FIELD)
    @Retention(RetentionPolicy.RUNTIME)
    public @interface Desc {
    
        String value();
    
        String remark() default "";
    
    }

package com.zyq.util;
    
    import java.lang.reflect.Field;
    import java.util.*;
    
    import com.zyq.annotation.Desc;
    import com.zyq.entity.vo.DescAttr;
    
    /**
     * 常量注解工具类
     * 
     * @author ZhangYuanqiang
     * @since 2021年4月14日
     */
    public class DescUtil {
    
        /**
         * 获取打了Desc注解类的字典属性列表
         * 
         * @param cls_指定类
         * @return 字典属性列表
         */
        public static <T> List<DescAttr> getAttrList(Class<T> cls) {
            try {
                Field[] fields = cls.getDeclaredFields();
                List<DescAttr> attrList = new LinkedList<>();
                for (Field field : fields) {
                    Desc desc = field.getAnnotation(Desc.class);
                    if (desc != null) {
                        DescAttr vo = new DescAttr();
                        vo.setKey(field.getInt(cls));
                        vo.setValue(desc.value());
                        vo.setRemark(desc.remark());
                        attrList.add(vo);
                    }
                }
                return attrList;
            } catch (Exception e) {
                e.printStackTrace();
            }
            return Collections.emptyList();
        }
    
        /**
         * 获取某个属性值的Desc注解
         *
         * @param cls_类
         * @param key_属性值
         * @return 注解
         */
        private static <T> Desc getDesc(Class<T> cls, int key) {
            Field[] fields = cls.getDeclaredFields();
            for (Field field : fields) {
                int i = 0;
                try {
                    i = field.getInt(cls);
                } catch (Exception e) {
                    e.printStackTrace();
                }
                if (i == key) {
                    return field.getAnnotation(Desc.class);
                }
            }
            return null;
        }
    
        /**
         * 获取某个属性值的Desc注解的Value值
         *
         * @param cls_类
         * @param key_属性值
         * @return 注解
         */
        public static <T> String getValue(Class<T> cls, int key) {
            Desc desc = DescUtil.getDesc(cls, key);
            if (desc != null) {
                return desc.value();
            }
            return "";
        }
    
        public static <T> boolean isContainKey(Class<T> cls, int key) {
            return !Objects.isNull(DescUtil.getDesc(cls, key));
        }
    
    }

package com.zyq.entity.vo;
    
    import lombok.Data;
    
    /**
     * Desc 注解解析后的实体
     * 
     * @author ZhangYuanqiang
     * @since 2021年4月14日
     */
    @Data
    public class DescAttr {
    
        public int key;
        public String value;
        public String remark;
    
    }