Back up maven-bundle-plugin to 3.5.1 since 4.0.0 and up require Java 8.
MODIFY
pom.xml
pom.xml
@@ -250,6 +250,8 @@ file comparators, endian transformation classes, and much more.
<properties>
<maven.compiler.source>1.7</maven.compiler.source>
<maven.compiler.target>1.7</maven.compiler.target>
+ <!-- version 4.0.0 requires Java 8 -->
+ <commons.felix.version>3.5.1</commons.felix.version>
<commons.componentid>io</commons.componentid>
<commons.module.name>org.apache.commons.io</commons.module.name>
<commons.rc.version>RC1</commons.rc.version>

Back up maven-bundle-plugin to 3.5.1 since 4.0.0 and up require Java 8.