Change the usage of properties to control
javaVersion.
diff --git a/pom.xml b/pom.xml
index 26f8d5e..7adb4c4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -80,8 +80,7 @@
   <properties>
     <mavenArchiverVersion>3.2.0</mavenArchiverVersion>
     <mavenVersion>3.0</mavenVersion>
-    <maven.compiler.target>1.7</maven.compiler.target>
-    <maven.compiler.source>1.7</maven.compiler.source>
+    <javaVersion>7</javaVersion>
     <surefire.version>2.21.0</surefire.version>
   </properties>