public static Field getDeclaredField(Class<?> clazz, String fieldName) throws SecurityException {
		if (null == clazz || StrUtil.isBlank(fieldName)) {
			return null;
		}
		try {
			return clazz.getDeclaredField(fieldName);
		} catch (NoSuchFieldException e) {
			// e.printStackTrace();
		}
		return null;
	}
@Test
	public void getDeclaredField() {
		Field noField = ClassUtil.getDeclaredField(TestSubClass.class, "noField");
		assertNull(noField);

		// 获取不到父类字段
		Field field = ClassUtil.getDeclaredField(TestSubClass.class, "field");
		assertNull(field);

		Field subField = ClassUtil.getDeclaredField(TestSubClass.class, "subField");
		assertNotNull(subField);
	}