Add Checkstyle rule for extends/implements
<property name="format" value="\n\n\Z" />
<property name="message" value="Blank line before end of file" />
</module>
+ <module name="RegexpSingleline">
+ <property name="format" value="(class|interface) ([a-zA-Z0-9_])+(&lt;.*&gt;)? (extends|implements)" />
+ <property name="message" value="No new line before extends/implements" />
+ </module>
<module name="RegexpSingleline">
<property name="format" value="Preconditions\.checkNotNull" />
<property name="message" value="Use java.util.Objects.requireNonNull instead of Preconditions\.checkNotNull" />
