After keep for public api, I can't include classes belonging to a sub package, see com.example.protocol.* below
<keep>
<class classes="protected"
methods="protected"
fields="protected">
</class>
<!------------------- this part doesn't work ----------------------------->
<class>
<patternset>
<include name="com.example.protocol.*"/>
</patternset>
</class>
</keep>
Tried above pom.xml but resulting class is still obfuscated