[
https://issues.apache.org/jira/browse/TINKERPOP-2005?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16563747#comment-16563747
]
ASF GitHub Bot commented on TINKERPOP-2005:
-------------------------------------------
Github user dimas-b commented on a diff in the pull request:
https://github.com/apache/tinkerpop/pull/899#discussion_r206549700
--- Diff:
gremlin-server/src/main/java/org/apache/tinkerpop/gremlin/server/ResponseHandlerContext.java
---
@@ -0,0 +1,85 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements. See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership. The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License. You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied. See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+package org.apache.tinkerpop.gremlin.server;
+
+import org.apache.tinkerpop.gremlin.driver.message.ResponseMessage;
+import org.apache.tinkerpop.gremlin.driver.message.ResponseStatusCode;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+import java.util.concurrent.atomic.AtomicBoolean;
+
+/**
+ * A context for asynchronously writing response messages related to a
particular request.
+ * <p>The "write" methods of this class ensure that at most one {@link
ResponseStatusCode#isFinalResponse() final}
+ * response message is written to the underlying channel. Attempts to
write more than one final response message will
+ * be ignored with a warning log message.</p>
+ * <p>Note: an object of this class should be used instead of writing to
the channel directly when multiple threads
+ * are expected to produce final response messages concurrently. Callers
must ensure that the same
+ * {@link ResponseHandlerContext} is used by all threads writing response
messages for the same request.</p>
+ *
+ * @author Dmitri Bourlatchkov
+ */
+public class ResponseHandlerContext {
+ private static final Logger logger =
LoggerFactory.getLogger(ResponseHandlerContext.class);
+
+ private final Context context;
+ private final AtomicBoolean finalResponseWritten = new AtomicBoolean();
+
+ public ResponseHandlerContext(Context context) {
--- End diff --
Sorry, missed that. Fixed in 63ae13c24.
> Intermittent NullPointerException in response handling
> ------------------------------------------------------
>
> Key: TINKERPOP-2005
> URL: https://issues.apache.org/jira/browse/TINKERPOP-2005
> Project: TinkerPop
> Issue Type: Improvement
> Components: driver
> Affects Versions: 3.2.9
> Reporter: stephen mallette
> Priority: Minor
>
> This stacktrace was reported to me:
> {code}
> 06:11:01 2018-07-05 13:11:01,706 ERROR 13:11:01,618 Could not process the
> response
> 06:11:01 java.lang.NullPointerException: null
> 06:11:01 at
> org.apache.tinkerpop.gremlin.driver.Handler$GremlinResponseHandler.lambda$channelRead0$39(Handler.java:220)
> 06:11:01 at java.util.ArrayList.forEach(ArrayList.java:1257)
> 06:11:01 at
> org.apache.tinkerpop.gremlin.driver.Handler$GremlinResponseHandler.channelRead0(Handler.java:220)
> 06:11:01 at
> org.apache.tinkerpop.gremlin.driver.Handler$GremlinResponseHandler.channelRead0(Handler.java:197)
> 06:11:01 at
> io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
> 06:11:01 at
> org.apache.tinkerpop.gremlin.driver.Handler$GremlinSaslAuthenticationHandler.channelRead0(Handler.java:123)
> 06:11:01 at
> org.apache.tinkerpop.gremlin.driver.Handler$GremlinSaslAuthenticationHandler.channelRead0(Handler.java:67)
> 06:11:01 at
> io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
> 06:11:01 at
> io.netty.handler.codec.MessageToMessageDecoder.channelRead(MessageToMessageDecoder.java:102)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
> 06:11:01 at
> org.apache.tinkerpop.gremlin.driver.handler.WebSocketClientHandler.channelRead0(WebSocketClientHandler.java:94)
> 06:11:01 at
> io.netty.channel.SimpleChannelInboundHandler.channelRead(SimpleChannelInboundHandler.java:105)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
> 06:11:01 at
> io.netty.handler.codec.ByteToMessageDecoder.fireChannelRead(ByteToMessageDecoder.java:310)
> 06:11:01 at
> io.netty.handler.codec.ByteToMessageDecoder.channelRead(ByteToMessageDecoder.java:284)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.fireChannelRead(AbstractChannelHandlerContext.java:340)
> 06:11:01 at
> io.netty.channel.DefaultChannelPipeline$HeadContext.channelRead(DefaultChannelPipeline.java:1334)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:362)
> 06:11:01 at
> io.netty.channel.AbstractChannelHandlerContext.invokeChannelRead(AbstractChannelHandlerContext.java:348)
> 06:11:01 at
> io.netty.channel.DefaultChannelPipeline.fireChannelRead(DefaultChannelPipeline.java:926)
> 06:11:01 at
> io.netty.channel.nio.AbstractNioByteChannel$NioByteUnsafe.read(AbstractNioByteChannel.java:134)
> 06:11:01 at
> io.netty.channel.nio.NioEventLoop.processSelectedKey(NioEventLoop.java:644)
> 06:11:01 at
> io.netty.channel.nio.NioEventLoop.processSelectedKeysOptimized(NioEventLoop.java:579)
> 06:11:01 at
> io.netty.channel.nio.NioEventLoop.processSelectedKeys(NioEventLoop.java:496)
> 06:11:01 at io.netty.channel.nio.NioEventLoop.run(NioEventLoop.java:458)
> 06:11:01 at
> io.netty.util.concurrent.SingleThreadEventExecutor$5.run(SingleThreadEventExecutor.java:858)
> 06:11:01 at java.lang.Thread.run(Thread.java:748)
> {code}
> Some initial investigation seems to indicate that it is intermittent and
> likely some form of timing issue. Will probably be hard to recreate. Hesitant
> to just make the problem go away without understanding why it is happening.
--
This message was sent by Atlassian JIRA
(v7.6.3#76005)
