--- pom.xml
+++ pom.xml
@@ -182,6 +182,7 @@
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <project.source.level>1.6</project.source.level>
         <project.target.level>1.6</project.target.level>
+        <maven.compiler.release>6</maven.compiler.release>
     </properties>
     
   <profiles>