JAVA通过反射获取和设置Bean属性(总结)

﹏ヽ暗。殇╰゛Y 2023-10-04 10:09 20阅读 0赞

获取/设置Bean属性

package utils;
    
    import lombok.extern.slf4j.Slf4j;
    import java.lang.reflect.Field;
    import java.lang.reflect.Method;
    import java.util.ArrayList;
    import java.util.List;
    import java.util.Map;
    import java.util.stream.Collectors;
    
    @Slf4j
    public class ObjectFiledUtil{
        
        
        /**
         * get field from T
         * @param obj T
         * @param fieldName field name
         * @return object
         */
        public static <T> Object getObjectField(T obj, String fieldName){
        
            if(null == obj) return null;
            Object object = null;
            try {
        
                //get the name of the property get method
                fieldName = fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
                Method method = obj.getClass().getMethod("get" + fieldName);
                object = method.invoke(obj);
            } catch (Exception e) {
        
                log.error("get object field from T error", e);
            }
            return object;
        }
    
        /**
         * get field from T list
         * @param list list
         * @param fieldName field name
         * @return object list
         */
        public static <T> List<Object> getObjectListField(List<T> list, String fieldName){
        
            if(null == list || list.size() == 0) return new ArrayList<>();
            List<Object> fieldList = new ArrayList<>();
            try {
        
                //get the name of the property get method
                fieldName = fieldName.substring(0, 1).toUpperCase() + fieldName.substring(1);
                for(T t : list){
        
                    Method m = t.getClass().getMethod("get" + fieldName);
                    fieldList.add(m.invoke(t));
                }
            } catch (Exception e) {
        
                log.error("get object list field from T error", e);
            }
            return fieldList;
        }
    
        /**
         * set a single field value for T
         * @param obj T
         * @param fieldName field name
         * @param value field value
         */
        public static <T> void setObjectField(T obj, String fieldName, T value){
        
            if(null == obj) return;
            try {
        
                Field field = obj.getClass().getDeclaredField(fieldName); //get attribute
                if(null != field){
        
                    field.setAccessible(true); //set accessibility
                    field.set(obj, value);//set attribute value
                }
            } catch (Exception e) {
        
                log.error("set object field to T error", e);
            }
        }
    
        /**
         * set field value for T batch
         * @param obj T
         * @param map key:filed name, value:filed value
         */
        public static <T> void setObjectFieldBatch(T obj, Map<String, Object> map){
        
            if(null == obj) return;
            try {
        
                for(String key : map.keySet()){
        
                    Field field = obj.getClass().getDeclaredField(key); //get attribute
                    if(null != field){
        
                        field.setAccessible(true); //set accessibility
                        field.set(obj, map.get(key));//set attribute value
                    }
                }
            } catch (Exception e) {
        
                log.error("set object field to T error", e);
            }
        }
    
        /**
         * set field value for T list batch
         * @param list list T
         * @param map key:filed name, value:filed value
         */
        public static <T> void setObjectFieldBatch(List<T> list, Map<String, Object> map){
        
            if(null == list || list.size() == 0) return;
            try {
        
                for(T t : list){
        
                    setObjectFieldBatch(t, map);
                }
            } catch (Exception e) {
        
                log.error("set object field to T error", e);
            }
        }
    
        /**
         * List<Object> to List<String>
         * @param list list
         * @return list
         */
        public static List<String> getStringListByObjectList(List<Object> list){
        
            if(null == list || list.size() == 0) return new ArrayList<>();
            return list.stream().map(String::valueOf).collect(Collectors.toList());
        }
    
    }