### Question:
ApiHandlerHelpers { public static FullHttpResponse notFoundResponse(ByteBuf outputBuffer, String content) { return createResponse(outputBuffer, content, NOT_FOUND); }  static boolean validateMethod(HttpRequest request, HttpMethod expectedMethod); static String validateContentType(HttpRequest request, String expectedContentType); static boolean validateAccessToken(HttpRequest request); static FullHttpResponse successResponse(ByteBuf outputBuffer, String content); static FullHttpResponse methodNotAllowedResponse(); static FullHttpResponse badRequestResponse(ByteBuf outputBuffer, String content); static FullHttpResponse unauthorizedResponse(ByteBuf outputBuffer, String content); static FullHttpResponse notFoundResponse(ByteBuf outputBuffer, String content); static FullHttpResponse internalServerErrorResponse(ByteBuf outputBuffer, String content);  }### Answer:
@Test public void testNotFoundResponseByteBufAndContentIsNull() { defaultResponse = new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND); assertEquals(defaultResponse, ApiHandlerHelpers.notFoundResponse(null, null)); }
@Test public void testNotFoundResponse() { FullHttpResponse res = new DefaultFullHttpResponse(HTTP_1_1, NOT_FOUND, byteBuf); HttpUtil.setContentLength(res, byteBuf.readableBytes()); assertEquals(res, ApiHandlerHelpers.notFoundResponse(byteBuf, content)); }