### Question:
SimpleContentTypeResolver implements ContentTypeResolver { public String getContentType(final String requestUrl) { final String extension = requestUrl.substring(requestUrl.lastIndexOf('.')); return mimeTypes.get(extension); } SimpleContentTypeResolver(); String getContentType(final String requestUrl);  }### Answer:
@Test public void testGetContentTypeOfCssUrlReturnsTextCss() { assertEquals("text/css", resolver.getContentType(CSS_URL)); }
@Test public void testGetContentTypeOfJsUrlReturnsApplicationXJavaScript() { assertEquals("application/x-javascript", resolver.getContentType(JS_URL)); }