@Test(expected = UnsupportedOperationException.class)
public void listShouldBeunmodifiableList(){

	// Given
	ContentType xmlContentType = ContentType.createContentType("application/xml");
	ContentType jsonContentType = ContentType.createContentType("application/json");
	ContentType rssXmlContentType = ContentType.createContentType("application/rss+xml");
	ContentTypes contentTypes = new ContentTypes(xmlContentType, jsonContentType, rssXmlContentType);
	List<ContentType> list = contentTypes.getListOfContentTypes();
	// When & Then
	list.add(xmlContentType);
}