public static <K, V> String joinIgnoreNull(Map<K, V> map, String separator, String keyValueSeparator, String... otherParams) {
		return join(map, separator, keyValueSeparator, true, otherParams);
	}
@Test
	public void joinIgnoreNullTest() {
		final Dict v1 = Dict.of().set("id", 12).set("name", "张三").set("age", null);
		final String s = MapUtil.joinIgnoreNull(v1, ",", "=");
		assertEquals("id=12,name=张三", s);
	}