code: public static List<Field> getRelatedColumns(Class<?> clazz) {
  		if(clazz == null) {
  			return new ArrayList<Field>();
  		}
  		
  		List<Class<?>> classLink = new ArrayList<Class<?>>();
  		Class<?> curClass = clazz;
  		while (curClass != null) {
  			classLink.add(curClass);
  			curClass = curClass.getSuperclass();
  		}
  		// 父类优先
  		List<Field> result = new ArrayList<Field>();
  		for (int i = classLink.size() - 1; i >= 0; i--) {
  			Field[] fields = classLink.get(i).getDeclaredFields();
  			for (Field field : fields) {
  				if (field.getAnnotation(RelatedColumn.class) != null) {
  					result.add(field);
  				}
  			}
  		}
  
  		return result;
  	}
docs: 获得所有有@RelatedColumn注解的列，包括继承的父类中的，顺序父类先
  
  @param clazz
  @return 不会返回null