This closes #1013

artemis-core-client/src/main/java/org/apache/activemq/artemis/core/remoting/impl/netty/NettyConnector.java

@@ -80,6 +80,7 @@ import io.netty.handler.codec.http.HttpResponse;
 import io.netty.handler.codec.http.HttpResponseDecoder;
 import io.netty.handler.codec.http.HttpResponseStatus;
 import io.netty.handler.codec.http.HttpVersion;
+import io.netty.handler.codec.http.LastHttpContent;
 import io.netty.handler.codec.http.cookie.ClientCookieEncoder;
 import io.netty.handler.ssl.SslHandler;
 import io.netty.util.AttributeKey;
@@ -745,12 +746,21 @@ public class NettyConnector extends AbstractConnector {
          this.httpClientCodec = httpClientCodec;
       }
 
+      /**
+       * HTTP upgrade response will be decode by Netty as 2 objects:
+       * - 1 HttpObject corresponding to the 101 SWITCHING PROTOCOL headers
+       * - 1 EMPTY_LAST_CONTENT
+       *
+       * The HTTP upgrade is successful whne the 101 SWITCHING PROTOCOL has been received (handshakeComplete = true)
+       * but the latch is count down only when the following EMPTY_LAST_CONTENT is also received.
+       * Otherwise this ChannelHandler would be removed too soon and the ActiveMQChannelHandler would handle the
+       * EMPTY_LAST_CONTENT (while it is expecitng only ByteBuf).
+       */
       @Override
       public void channelRead0(ChannelHandlerContext ctx, HttpObject msg) throws Exception {
          if (logger.isDebugEnabled()) {
             logger.debug("Received msg=" + msg);
          }
-         try {
          if (msg instanceof HttpResponse) {
             HttpResponse response = (HttpResponse) msg;
             if (response.getStatus().code() == HttpResponseStatus.SWITCHING_PROTOCOLS.code() && response.headers().get(HttpHeaders.Names.UPGRADE).equals(ACTIVEMQ_REMOTING)) {
@@ -758,24 +768,29 @@ public class NettyConnector extends AbstractConnector {
                String expectedResponse = createExpectedResponse(MAGIC_NUMBER, ctx.channel().attr(REMOTING_KEY).get());
 
                if (expectedResponse.equals(accept)) {
+                  // HTTP upgrade is successful but let's wait to receive the EMPTY_LAST_CONTENT to count down the latch
+                  handshakeComplete = true;
+               } else {
+                  // HTTP upgrade failed
+                  ActiveMQClientLogger.LOGGER.httpHandshakeFailed(msg);
+                  ctx.close();
+                  latch.countDown();
+               }
+               return;
+            }
+         } else if (msg == LastHttpContent.EMPTY_LAST_CONTENT && handshakeComplete) {
             // remove the http handlers and flag the activemq channel handler as active
             pipeline.remove(httpClientCodec);
             pipeline.remove(this);
-                     handshakeComplete = true;
             ActiveMQChannelHandler channelHandler = pipeline.get(ActiveMQChannelHandler.class);
             channelHandler.active = true;
-                     return;
          }
-               }
-            }
-         } finally {
          if (!handshakeComplete) {
             ActiveMQClientLogger.LOGGER.httpHandshakeFailed(msg);
             ctx.close();
          }
          latch.countDown();
       }
-      }
 
       @Override
       public void exceptionCaught(ChannelHandlerContext ctx, Throwable cause) throws Exception {