public static String addPrefixIfNot(CharSequence str, CharSequence prefix) {
		return prependIfMissing(str, prefix, prefix);
	}
@Test
	public void addPrefixIfNotTest() {
		String str = "hutool";
		String result = CharSequenceUtil.addPrefixIfNot(str, "hu");
		assertEquals(str, result);

		result = CharSequenceUtil.addPrefixIfNot(str, "Good");
		assertEquals("Good" + str, result);
	}