resolve issue
@@ -375,6 +375,7 @@ This license is based on the Apache Software License, version 1.1.</extractedTex
<version>2.9</version>
<configuration>
<quiet>true</quiet>
+ <source>8</source>
<additionalparam>-Xdoclint:none</additionalparam>
</configuration>
<executions>
