Bug commit from the following repository apache/rocketmq

This bug commit is a reflect of source code from: http://github.com/apache/rocketmq/commit/ce06e292a3a57b518e571f2747ddb66b566d3d7e.

.gitignore

@@ -0,0 +1,13 @@
+*dependency-reduced-pom.xml
+.classpath
+.project
+.settings/
+target/
+devenv
+*.log*
+*.iml
+.idea/
+*.versionsBackup
+!NOTICE-BIN
+!LICENSE-BIN
+.DS_Store

.travis.yml

@@ -0,0 +1,30 @@
+notifications:
+  email:
+    recipients:
+      - dev@rocketmq.apache.org
+  on_success: change
+  on_failure: always
+
+language: java
+
+matrix:
+  include:
+  # On OSX, run with default JDK only.
+  # - os: osx
+  # On Linux, run with specific JDKs only.
+  - os: linux
+    env: CUSTOM_JDK="oraclejdk8"
+
+before_install:
+  - echo 'MAVEN_OPTS="$MAVEN_OPTS -Xmx1024m -XX:MaxPermSize=512m -XX:+BytecodeVerificationLocal"' >> ~/.mavenrc
+  - cat ~/.mavenrc
+  - if [ "$TRAVIS_OS_NAME" == "osx" ]; then export JAVA_HOME=$(/usr/libexec/java_home); fi
+  - if [ "$TRAVIS_OS_NAME" == "linux" ]; then jdk_switcher use "$CUSTOM_JDK"; fi
+
+script:
+  - travis_retry mvn -B clean apache-rat:check
+  - travis_retry mvn -B package jacoco:report coveralls:report
+
+after_success:
+  - mvn clean install -Pit-test
+  - mvn sonar:sonar -Psonar-apache

BUILDING

@@ -0,0 +1,37 @@
+Build Instructions for Apache RocketMQ
+
+====================================================
+
+(1) Prerequisites
+
+    JDK 1.7+ is required in order to compile and run RocketMQ.
+
+    RocketMQ utilizes Maven as a distribution management and packaging tool. Version 3.0.3 or later is required.
+    Maven installation and configuration instructions can be found here:
+
+    http://maven.apache.org/run-maven/index.html
+
+
+(2) Run test cases
+
+    Execute the following command in order to compile and run test cases of each components:
+
+    $ mvn test
+
+
+(3) Import projects to Eclipse IDE
+
+    First, generate eclipse project files:
+
+    $ mvn -U eclipse:eclipse
+
+    Then, import to eclipse by specifying the root directory of the project via:
+
+    [File] > [Import] > [Existing Projects into Workspace].
+
+
+(4) Build distribution packages
+
+    Execute the following command in order to build the tar.gz packages and install JAR into local repository:
+
+    $ mvn -Prelease-all -DskipTests clean install -U

CONTRIBUTING.md

@@ -0,0 +1,32 @@
+## How To Contribute
+
+We are always very happy to have contributions, whether for trivial cleanups or big new features.
+We want to have high quality, well documented codes for each programming language, as well as the surrounding [ecosystem](https://github.com/apache/rocketmq-externals) of integration tools that people use with RocketMQ.
+
+Nor is code the only way to contribute to the project. We strongly value documentation, integration with other project, and gladly accept improvements for these aspects.
+
+## Contributing code
+
+To submit a change for inclusion, please do the following:
+
+#### If the change is non-trivial please include some unit tests that cover the new functionality.
+#### If you are introducing a completely new feature or API it is a good idea to start a wiki and get consensus on the basic design first.
+#### It is our job to follow up on patches in a timely fashion. Nag us if we aren't doing our job (sometimes we drop things).
+
+## Becoming a Committer
+
+We are always interested in adding new contributors. What we look for are series of contributions, good taste and ongoing interest in the project. If you are interested in becoming a committer, please let one of the existing committers know and they can help you walk through the process.
+
+Nowadays,we have several important contribution points:
+#### Wiki & JavaDoc
+#### RocketMQ Console
+#### RocketMQ SDK(C++\.Net\Php\Python\Go\Node.js)
+#### RocketMQ MySQL(Oracle\PostgreSQL\Redis\MongoDB\HBase\MSSQL) Replicator
+
+##### Prerequisite
+If you want to contribute the above listing points, you must abide our some prerequisites:
+
+###### Readability - API must have Javadoc,some very important methods also must have javadoc
+###### Testability - 80% above unit test coverage about main process
+###### Maintainability - Comply with our [checkstyle spec](style/rmq_checkstyle.xml), and at least 3 month update frequency
+###### Deployability - We encourage you to deploy into [maven repository](http://search.maven.org/)

LICENSE

@@ -0,0 +1,201 @@
+                                 Apache License
+                           Version 2.0, January 2004
+                        http://www.apache.org/licenses/
+
+   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
+
+   1. Definitions.
+
+      "License" shall mean the terms and conditions for use, reproduction,
+      and distribution as defined by Sections 1 through 9 of this document.
+
+      "Licensor" shall mean the copyright owner or entity authorized by
+      the copyright owner that is granting the License.
+
+      "Legal Entity" shall mean the union of the acting entity and all
+      other entities that control, are controlled by, or are under common
+      control with that entity. For the purposes of this definition,
+      "control" means (properties) the power, direct or indirect, to cause the
+      direction or management of such entity, whether by contract or
+      otherwise, or (ii) ownership of fifty percent (50%) or more of the
+      outstanding shares, or (iii) beneficial ownership of such entity.
+
+      "You" (or "Your") shall mean an individual or Legal Entity
+      exercising permissions granted by this License.
+
+      "Source" form shall mean the preferred form for making modifications,
+      including but not limited to software source code, documentation
+      source, and configuration files.
+
+      "Object" form shall mean any form resulting from mechanical
+      transformation or translation of a Source form, including but
+      not limited to compiled object code, generated documentation,
+      and conversions to other media types.
+
+      "Work" shall mean the work of authorship, whether in Source or
+      Object form, made available under the License, as indicated by a
+      copyright notice that is included in or attached to the work
+      (an example is provided in the Appendix below).
+
+      "Derivative Works" shall mean any work, whether in Source or Object
+      form, that is based on (or derived from) the Work and for which the
+      editorial revisions, annotations, elaborations, or other modifications
+      represent, as a whole, an original work of authorship. For the purposes
+      of this License, Derivative Works shall not include works that remain
+      separable from, or merely link (or bind by name) to the interfaces of,
+      the Work and Derivative Works thereof.
+
+      "Contribution" shall mean any work of authorship, including
+      the original version of the Work and any modifications or additions
+      to that Work or Derivative Works thereof, that is intentionally
+      submitted to Licensor for inclusion in the Work by the copyright owner
+      or by an individual or Legal Entity authorized to submit on behalf of
+      the copyright owner. For the purposes of this definition, "submitted"
+      means any form of electronic, verbal, or written communication sent
+      to the Licensor or its representatives, including but not limited to
+      communication on electronic mailing lists, source code control systems,
+      and issue tracking systems that are managed by, or on behalf of, the
+      Licensor for the purpose of discussing and improving the Work, but
+      excluding communication that is conspicuously marked or otherwise
+      designated in writing by the copyright owner as "Not a Contribution."
+
+      "Contributor" shall mean Licensor and any individual or Legal Entity
+      on behalf of whom a Contribution has been received by Licensor and
+      subsequently incorporated within the Work.
+
+   2. Grant of Copyright License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      copyright license to reproduce, prepare Derivative Works of,
+      publicly display, publicly perform, sublicense, and distribute the
+      Work and such Derivative Works in Source or Object form.
+
+   3. Grant of Patent License. Subject to the terms and conditions of
+      this License, each Contributor hereby grants to You a perpetual,
+      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
+      (except as stated in this section) patent license to make, have made,
+      use, offer to sell, sell, import, and otherwise transfer the Work,
+      where such license applies only to those patent claims licensable
+      by such Contributor that are necessarily infringed by their
+      Contribution(s) alone or by combination of their Contribution(s)
+      with the Work to which such Contribution(s) was submitted. If You
+      institute patent litigation against any entity (including a
+      cross-claim or counterclaim in a lawsuit) alleging that the Work
+      or a Contribution incorporated within the Work constitutes direct
+      or contributory patent infringement, then any patent licenses
+      granted to You under this License for that Work shall terminate
+      as of the date such litigation is filed.
+
+   4. Redistribution. You may reproduce and distribute copies of the
+      Work or Derivative Works thereof in any medium, with or without
+      modifications, and in Source or Object form, provided that You
+      meet the following conditions:
+
+      (a) You must give any other recipients of the Work or
+          Derivative Works a copy of this License; and
+
+      (b) You must cause any modified files to carry prominent notices
+          stating that You changed the files; and
+
+      (c) You must retain, in the Source form of any Derivative Works
+          that You distribute, all copyright, patent, trademark, and
+          attribution notices from the Source form of the Work,
+          excluding those notices that do not pertain to any part of
+          the Derivative Works; and
+
+      (d) If the Work includes a "NOTICE" text file as part of its
+          distribution, then any Derivative Works that You distribute must
+          include a readable copy of the attribution notices contained
+          within such NOTICE file, excluding those notices that do not
+          pertain to any part of the Derivative Works, in at least one
+          of the following places: within a NOTICE text file distributed
+          as part of the Derivative Works; within the Source form or
+          documentation, if provided along with the Derivative Works; or,
+          within a display generated by the Derivative Works, if and
+          wherever such third-party notices normally appear. The contents
+          of the NOTICE file are for informational purposes only and
+          do not modify the License. You may add Your own attribution
+          notices within Derivative Works that You distribute, alongside
+          or as an addendum to the NOTICE text from the Work, provided
+          that such additional attribution notices cannot be construed
+          as modifying the License.
+
+      You may add Your own copyright statement to Your modifications and
+      may provide additional or different license terms and conditions
+      for use, reproduction, or distribution of Your modifications, or
+      for any such Derivative Works as a whole, provided Your use,
+      reproduction, and distribution of the Work otherwise complies with
+      the conditions stated in this License.
+
+   5. Submission of Contributions. Unless You explicitly state otherwise,
+      any Contribution intentionally submitted for inclusion in the Work
+      by You to the Licensor shall be under the terms and conditions of
+      this License, without any additional terms or conditions.
+      Notwithstanding the above, nothing herein shall supersede or modify
+      the terms of any separate license agreement you may have executed
+      with Licensor regarding such Contributions.
+
+   6. Trademarks. This License does not grant permission to use the trade
+      names, trademarks, service marks, or product names of the Licensor,
+      except as required for reasonable and customary use in describing the
+      origin of the Work and reproducing the content of the NOTICE file.
+
+   7. Disclaimer of Warranty. Unless required by applicable law or
+      agreed to in writing, Licensor provides the Work (and each
+      Contributor provides its Contributions) on an "AS IS" BASIS,
+      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
+      implied, including, without limitation, any warranties or conditions
+      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
+      PARTICULAR PURPOSE. You are solely responsible for determining the
+      appropriateness of using or redistributing the Work and assume any
+      risks associated with Your exercise of permissions under this License.
+
+   8. Limitation of Liability. In no event and under no legal theory,
+      whether in tort (including negligence), contract, or otherwise,
+      unless required by applicable law (such as deliberate and grossly
+      negligent acts) or agreed to in writing, shall any Contributor be
+      liable to You for damages, including any direct, indirect, special,
+      incidental, or consequential damages of any character arising as a
+      result of this License or out of the use or inability to use the
+      Work (including but not limited to damages for loss of goodwill,
+      work stoppage, computer failure or malfunction, or any and all
+      other commercial damages or losses), even if such Contributor
+      has been advised of the possibility of such damages.
+
+   9. Accepting Warranty or Additional Liability. While redistributing
+      the Work or Derivative Works thereof, You may choose to offer,
+      and charge a fee for, acceptance of support, warranty, indemnity,
+      or other liability obligations and/or rights consistent with this
+      License. However, in accepting such obligations, You may act only
+      on Your own behalf and on Your sole responsibility, not on behalf
+      of any other Contributor, and only if You agree to indemnify,
+      defend, and hold each Contributor harmless for any liability
+      incurred by, or claims asserted against, such Contributor by reason
+      of your accepting any such warranty or additional liability.
+
+   END OF TERMS AND CONDITIONS
+
+   APPENDIX: How to apply the Apache License to your work.
+
+      To apply the Apache License to your work, attach the following
+      boilerplate notice, with the fields enclosed by brackets "[]"
+      replaced with your own identifying information. (Don't include
+      the brackets!)  The text should be enclosed in the appropriate
+      comment syntax for the file format. We also recommend that a
+      file or class name and description of purpose be included on the
+      same "printed page" as the copyright notice for easier
+      identification within third-party archives.
+
+   Copyright [yyyy] [name of copyright owner]
+
+   Licensed 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.

NOTICE

@@ -0,0 +1,5 @@
+Apache RocketMQ
+Copyright 2016-2017 The Apache Software Foundation
+
+This product includes software developed at
+The Apache Software Foundation (http://www.apache.org/).

PULL_REQUEST_TEMPLATE.md

@@ -0,0 +1,20 @@
+## What is the purpose of the change
+
+XXXXX
+
+## Brief changelog
+
+XX
+
+## Verifying this change
+
+XXXX
+
+Follow this checklist to help us incorporate your contribution quickly and easily:
+
+- [x] Make sure there is a [JIRA issue](https://issues.apache.org/jira/projects/ROCKETMQ/issues/) filed for the change (usually before you start working on it). Trivial changes like typos do not require a JIRA issue. Your pull request should address just this issue, without pulling in other changes - one PR resolves one issue. 
+- [ ] Format the pull request title like `[ROCKETMQ-XXX] Fix UnknownException when host config not exist`. Each commit in the pull request should have a meaningful subject line and body.
+- [ ] Write a pull request description that is detailed enough to understand what the pull request does, how, and why.
+- [ ] Write necessary unit-test to verify your logic correction, more mock a little better when cross module dependency exist. If the new feature or significant change is committed, please remember to add integration-test in [test module](https://github.com/apache/rocketmq/tree/master/test).
+- [ ] Run `mvn -B clean apache-rat:check findbugs:findbugs checkstyle:checkstyle` to make sure basic checks pass. Run `mvn clean install -DskipITs` to make sure unit-test pass. Run `mvn clean test-compile failsafe:integration-test`  to make sure integration-test pass.
+- [ ] If this contribution is large, please file an [Apache Individual Contributor License Agreement](http://www.apache.org/licenses/#clas).

README.md

@@ -0,0 +1,48 @@
+## Apache RocketMQ [![Build Status](https://travis-ci.org/apache/rocketmq.svg?branch=master)](https://travis-ci.org/apache/rocketmq) [![Coverage Status](https://coveralls.io/repos/github/apache/rocketmq/badge.svg?branch=master)](https://coveralls.io/github/apache/rocketmq?branch=master)
+[![Maven Central](https://maven-badges.herokuapp.com/maven-central/org.apache.rocketmq/rocketmq-all/badge.svg)](http://search.maven.org/#search%7Cga%7C1%7Corg.apache.rocketmq)
+[![GitHub release](https://img.shields.io/badge/release-download-orange.svg)](https://rocketmq.apache.org/dowloading/releases)
+[![License](https://img.shields.io/badge/license-Apache%202-4EB1BA.svg)](https://www.apache.org/licenses/LICENSE-2.0.html)
+
+**[Apache RocketMQ](https://rocketmq.apache.org) is a distributed messaging and streaming platform with low latency, high performance and reliability, trillion-level capacity and flexible scalability.**
+
+It offers a variety of features:
+
+* Pub/Sub messaging model
+* Scheduled message delivery
+* Message retroactivity by time or offset
+* Log hub for streaming
+* Big data integration
+* Reliable FIFO and strict ordered messaging in the same queue
+* Efficient pull&push consumption model
+* Million-level message accumulation capacity in a single queue
+* Multiple messaging protocols like JMS and OpenMessaging
+* Flexible distributed scale-out deployment architecture
+* Lightning-fast batch message exchange system
+* Various message filter mechanics such as SQL and Tag
+* Docker images for isolated testing and cloud isolated clusters
+* Feature-rich administrative dashboard for configuration, metrics and monitoring
+
+
+----------
+
+## Learn it & Contact us
+* Mailing Lists: <https://rocketmq.apache.org/about/contact/>
+* Home: <https://rocketmq.apache.org>
+* Docs: <https://rocketmq.apache.org/docs/quick-start/>
+* Issues: <https://issues.apache.org/jira/browse/RocketMQ>
+* Ask: <https://stackoverflow.com/questions/tagged/rocketmq>
+
+
+----------
+
+## Apache RocketMQ Community
+* [RocketMQ Community Projects](https://github.com/apache/rocketmq-externals)
+
+----------
+
+## Contributing
+We always welcome new contributions, whether for trivial cleanups, big new features or other material rewards, more details see [here](http://rocketmq.apache.org/docs/how-to-contribute/) 
+
+----------
+## License
+[Apache License, Version 2.0](http://www.apache.org/licenses/LICENSE-2.0.html) Copyright (C) Apache Software Foundation