@Test // if the path is null, just add the value to the top level Map with a null key
public void putByPath_path_null() {

	Map<String,Object> input = new HashMap<String,Object>();
	Map<String,Object> expect = new HashMap<String,Object>() {{
		put(null, "value");
	}};
	CollectionUtils.putByPath(input, null, "value");
	assertEquals(expect, input);
}