Apache-rat integration.

	Builds will fail if there is a file with missing license header.
diff --git a/etc/rat-excludes b/etc/rat-excludes
new file mode 100644
index 0000000..787e20d
--- /dev/null
+++ b/etc/rat-excludes
@@ -0,0 +1,66 @@
+#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.
+#
+#GIT
+.git/**
+**/.gitignore
+**/.gitkeep
+#IDE
+etc/eclipse-java-google-style.xml
+etc/intellij-java-modified-google-style.xml
+etc/eclipseOrganizeImports.importorder
+**/.project
+**/.classpath
+**/.settings/**
+**/build-eclipse/**
+**/*.iml
+**/*.ipr
+**/*.iws
+.idea/**
+**/tags
+**/out/**
+
+# text files
+**/*.fig
+**/*.txt
+**/*.md
+**/*.json
+**/*.tx0
+**/*.txo
+**/*.log
+**/*.patch
+**/*.diff
+**/*.rej
+**/*.orig
+**/*.MF
+
+#binary files
+**/*.cer
+**/*.dia
+**/*.gfs
+**/*.gif
+**/*.ico
+**/*.jpg
+**/*.keystore
+**/*.pdf
+**/*.png
+**/*.ser
+**/*.svg
+**/*.truststore
+**/*.xls
+**/publickeyfile
+**/*.dat
+
+#other text files
+**/log4j*.xml
+**/META-INF/**
\ No newline at end of file
diff --git a/pom.xml b/pom.xml
index c795830..1b3a3a2 100644
--- a/pom.xml
+++ b/pom.xml
@@ -50,6 +50,7 @@
         <maven-plugin.version>3.8.1</maven-plugin.version>
         <zookeeper.version>3.5.7</zookeeper.version>
         <spotless.version>1.27.0</spotless.version>
+        <rat.version>0.13</rat.version>
         <confluent.maven.repo>http://packages.confluent.io/maven/</confluent.maven.repo>
     </properties>
 
@@ -194,6 +195,22 @@
                 </configuration>
             </plugin>
             <plugin>
+                <groupId>org.apache.rat</groupId>
+                <artifactId>apache-rat-plugin</artifactId>
+                <version>${rat.version}</version>
+                <executions>
+                    <execution>
+                        <phase>validate</phase>
+                        <goals>
+                            <goal>check</goal>
+                        </goals>
+                    </execution>
+                </executions>
+                <configuration>
+                    <excludesFile>etc/rat-excludes</excludesFile>
+                </configuration>
+            </plugin>
+            <plugin>
                 <groupId>io.confluent</groupId>
                 <version>0.10.0</version>
                 <artifactId>kafka-connect-maven-plugin</artifactId>
diff --git a/src/assembly/development.xml b/src/assembly/development.xml
index ae37239..05e196c 100644
--- a/src/assembly/development.xml
+++ b/src/assembly/development.xml
@@ -1,3 +1,20 @@
+<!--
+  ~ 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.
+  -->
+
 <assembly xmlns="http://maven.apache.org/ASSEMBLY/2.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://maven.apache.org/ASSEMBLY/2.0.0 http://maven.apache.org/xsd/assembly-2.0.0.xsd">
diff --git a/src/assembly/package.xml b/src/assembly/package.xml
index 9704986..852f07f 100644
--- a/src/assembly/package.xml
+++ b/src/assembly/package.xml
@@ -1,3 +1,20 @@
+<!--
+  ~ 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.
+  -->
+
 <assembly xmlns="http://maven.apache.org/ASSEMBLY/2.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://maven.apache.org/ASSEMBLY/2.0.0 http://maven.apache.org/xsd/assembly-2.0.0.xsd">
diff --git a/src/assembly/standalone.xml b/src/assembly/standalone.xml
index 9cf29e3..8f1c91b 100644
--- a/src/assembly/standalone.xml
+++ b/src/assembly/standalone.xml
@@ -1,3 +1,20 @@
+<!--
+  ~ 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.
+  -->
+
 <assembly xmlns="http://maven.apache.org/ASSEMBLY/2.0.0"
           xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
           xsi:schemaLocation="http://maven.apache.org/ASSEMBLY/2.0.0 http://maven.apache.org/xsd/assembly-2.0.0.xsd">