Feature/Style Check (#925)

* Create style check module.

* Add scm, licenses, mailing lists into root pom.

* Add jacoco and coveralls maven plugin into check style module’s pom.

apm-checkstyle/pom.xml

+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+  ~ 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.
+  ~
+  -->
+
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <parent>
+        <groupId>org.apache</groupId>
+        <artifactId>apache</artifactId>
+        <version>19</version>
+    </parent>
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>org.apache.skywalking</groupId>
+    <artifactId>apm-checkstyle</artifactId>
+    <version>5.0.0-alpha-SNAPSHOT</version>
+    <description>Module to hold Checkstyle for SkyWalking.</description>
+
+    <build>
+        <plugins>
+            <!-- 覆盖率 -->
+            <plugin>
+                <groupId>org.jacoco</groupId>
+                <artifactId>jacoco-maven-plugin</artifactId>
+                <version>0.7.9</version>
+                <executions>
+                    <execution>
+                        <id>prepare-agent</id>
+                        <goals>
+                            <goal>prepare-agent</goal>
+                        </goals>
+                    </execution>
+                </executions>
+            </plugin>
+            <plugin>
+                <groupId>org.eluder.coveralls</groupId>
+                <artifactId>coveralls-maven-plugin</artifactId>
+                <version>4.1.0</version>
+                <configuration>
+                    <repoToken>xFwR2GqmxcMxV7tGEpW2NfwIrbCD4cQCS</repoToken>
+                    <sourceDirectories>
+                        <sourceDirectory>${project.build.sourceDirectory}</sourceDirectory>
+                    </sourceDirectories>
+                </configuration>
+            </plugin>
+        </plugins>
+    </build>
+</project>
\ No newline at end of file

checkStyle.xml → apm-checkstyle/src/main/resources/skywalking/checkStyle.xml

@@ -28,11 +28,6 @@
     <!--To configure the check to report on the first instance in each file-->
     <module name="FileTabCharacter"/>
 
-    <!-- header -->
-    <module name="Header">
-        <property name="headerFile" value="CHECKSTYLE_HEAD"/>
-    </module>
-
     <module name="RegexpSingleline">
         <property name="format" value="System\.out\.println"/>
         <property name="message" value="Prohibit invoking System.out.println in source code !"/>

pom.xml

@@ -65,23 +65,54 @@
         <module>apm-protocol</module>
         <module>apm-webapp</module>
         <module>apm-dist</module>
+        <module>apm-checkstyle</module>
     </modules>
     <packaging>pom</packaging>
 
     <name>apm</name>
     <url>https://github.com/apache/incubator-skywalking</url>
 
+    <scm>
+        <url>https://github.com/apache/incubator-skywalking</url>
+        <connection>scm:git:https://github.com/apache/incubator-skywalking.git</connection>
+        <developerConnection>scm:git:https://github.com/apache/incubator-skywalking.git</developerConnection>
+        <tag>HEAD</tag>
+    </scm>
+
     <issueManagement>
         <system>GitHub</system>
         <url>https://github.com/apache/incubator-skywalking/issues</url>
     </issueManagement>
 
+    <licenses>
+        <license>
+            <name>The Apache Software License, Version 2.0</name>
+            <url>http://www.apache.org/licenses/LICENSE-2.0.txt</url>
+        </license>
+    </licenses>
+
+    <mailingLists>
+        <mailingList>
+            <name>SkyWalking Developer List</name>
+            <post>dev@skywalking.incubator.apache.org</post>
+            <subscribe>dev-subscribe@skywalking.incubator.apache.org</subscribe>
+            <unsubscribe>dev-unsubscribe@skywalking.incubator.apache.org</unsubscribe>
+        </mailingList>
+        <mailingList>
+            <name>SkyWalking Commits</name>
+            <post>commits@skywalking.incubator.apache.org</post>
+            <subscribe>commits-subscribe@skywalking.incubator.apache.org</subscribe>
+            <unsubscribe>commits-unsubscribe@skywalking.incubator.apache.org</unsubscribe>
+        </mailingList>
+    </mailingLists>
+
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <compiler.version>1.8</compiler.version>
         <scala.compiler.version>2.11.7</scala.compiler.version>
         <powermock.version>1.6.4</powermock.version>
         <docker.plugin.version>0.4.13</docker.plugin.version>
+        <checkstyle.version>6.18</checkstyle.version>
     </properties>
 
     <dependencies>
@@ -255,12 +286,20 @@
             <plugin>
                 <artifactId>maven-checkstyle-plugin</artifactId>
                 <version>2.17</version>
+                <dependencies>
+                    <dependency>
+                        <groupId>org.apache.skywalking</groupId>
+                        <artifactId>apm-checkstyle</artifactId>
+                        <version>${project.version}</version>
+                    </dependency>
+                </dependencies>
                 <executions>
                     <execution>
                         <id>validate</id>
                         <phase>validate</phase>
                         <configuration>
-                            <configLocation>checkStyle.xml</configLocation>
+                            <configLocation>skywalking/checkStyle.xml</configLocation>
+                            <headerLocation>skywalking/CHECKSTYLE_HEAD</headerLocation>
                             <encoding>UTF-8</encoding>
                             <consoleOutput>true</consoleOutput>
                             <includeTestSourceDirectory>true</includeTestSourceDirectory>
@@ -372,5 +411,5 @@
             </build>
         </profile>
     </profiles>
-    
+
 </project>