docs: public static Field getField(final Class clazz, final String fieldName) {
  		Validate.notNull(clazz, "clazz can't be null");
  		Validate.notEmpty(fieldName, "fieldName can't be blank");
  		for (Class<?> superClass = clazz; superClass != Object.class; superClass = superClass.getSuperclass()) {
  			try {
  				Field field = superClass.getDeclaredField(fieldName);
  				makeAccessible(field);
  				return field;
  			} catch (NoSuchFieldException e) {// NOSONAR
  				// Field不在当前类定义,继续向上转型
  			}
  		}
  		return null;
  	}