Wicketstuff core modules that require to be build using Java 7. Typically this is because of a Java 7 feature requirement or Java 7 compiled upstream dependency.
'org.wicketstuff:wicket-bundle-parent:7.0.0'
<dependency>
<groupId>org.wicketstuff</groupId>
<artifactId>wicket-bundle-parent</artifactId>
<version>7.0.0</version>
</dependency>
<dependency org="org.wicketstuff" name="wicket-bundle-parent" rev="7.0.0"/>
"org.wicketstuff", "wicket-bundle-parent", "7.0.0"