public static <T> void padRight(Collection<T> list, int minLen, T padObj) {
		Objects.requireNonNull(list);
		for (int i = list.size(); i < minLen; i++) {
			list.add(padObj);
		}
	}
@Test
	public void testPadRight() {
		final List<String> srcList = CollUtil.newArrayList("a");
		final List<String> answerList = CollUtil.newArrayList("a", "b", "b", "b", "b");
		CollUtil.padRight(srcList, 5, "b");
		assertEquals(srcList, answerList);
	}