### Question:
NettyMessageProcessor extends SimpleChannelInboundHandler<HttpObject> { private boolean isOpen() { return channelOpen.get() && ctx.channel().isActive(); } NettyMessageProcessor(NettyMetrics nettyMetrics, NettyConfig nettyConfig, PerformanceConfig performanceConfig,
      RestRequestHandler requestHandler); @Override void channelActive(ChannelHandlerContext ctx); @Override void channelInactive(ChannelHandlerContext ctx); @Override void exceptionCaught(ChannelHandlerContext ctx, Throwable cause); @Override void userEventTriggered(ChannelHandlerContext ctx, Object event); @Override void channelRead0(ChannelHandlerContext ctx, HttpObject obj);  }### Answer:
@Test public void requestHandleWithBadInputTest() throws IOException { String content = "@@randomContent@@@"; EmbeddedChannel channel = createChannel(); channel.writeInbound(new DefaultLastHttpContent(Unpooled.wrappedBuffer(content.getBytes()))); HttpResponse response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); assertFalse("Channel is not closed", channel.isOpen()); channel = createChannel(); channel.writeInbound(RestTestUtils.createRequest(HttpMethod.GET, MockRestRequestService.ECHO_REST_METHOD, null)); channel.writeInbound(LastHttpContent.EMPTY_LAST_CONTENT); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.OK, response.status()); while (channel.readOutbound() != null) { ; } assertTrue("Channel is not active", channel.isActive()); channel.writeInbound(LastHttpContent.EMPTY_LAST_CONTENT); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); assertFalse("Channel is not closed", channel.isOpen()); channel = createChannel(); channel.writeInbound(RestTestUtils.createRequest(HttpMethod.GET, "/", null)); channel.writeInbound(new DefaultLastHttpContent(Unpooled.wrappedBuffer(content.getBytes()))); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); assertFalse("Channel is not closed", channel.isOpen()); channel = createChannel(); channel.writeInbound(new DefaultHttpResponse(HttpVersion.HTTP_1_1, HttpResponseStatus.OK)); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); assertFalse("Channel is not closed", channel.isOpen()); channel = createChannel(); channel.writeInbound(RestTestUtils.createRequest(HttpMethod.GET, "/", null)); channel.writeInbound(RestTestUtils.createRequest(HttpMethod.GET, "/", null)); assertFalse("Channel is not closed", channel.isOpen()); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); channel = createChannel(); HttpRequest httpRequest = RestTestUtils.createRequest(HttpMethod.GET, "/", null); httpRequest.setDecoderResult(DecoderResult.failure(new IllegalStateException("Induced failure"))); channel.writeInbound(httpRequest); assertFalse("Channel is not closed", channel.isOpen()); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); channel = createChannel(); channel.writeInbound(RestTestUtils.createRequest(HttpMethod.TRACE, "/", null)); assertFalse("Channel is not closed", channel.isOpen()); response = (HttpResponse) channel.readOutbound(); assertEquals("Unexpected response status", HttpResponseStatus.BAD_REQUEST, response.status()); }