### Question:
ErrorUtils { public static String getGatewayUri(HttpServletRequest request) { return (String) request.getAttribute(RequestDispatcher.FORWARD_REQUEST_URI); } private  ErrorUtils(); static int getErrorStatus(HttpServletRequest request); static String getErrorMessage(HttpServletRequest request); static String getGatewayUri(HttpServletRequest request); static final String ATTR_ERROR_EXCEPTION; }### Answer:
@Test void testGetGatewayUri() { MockHttpServletRequest request = new MockHttpServletRequest(); assertEquals(null, ErrorUtils.getGatewayUri(request)); request.setAttribute(RequestDispatcher.FORWARD_REQUEST_URI, "/uri"); assertEquals("/uri", ErrorUtils.getGatewayUri(request)); }