It will not generate the XSD classes when you run mvn clean compile package, as generate-sources is not part of the packaging goal.
The default bindings for WAR packaging would be
process-resources
compile
process-test-resources
test-compile
test
package
install
deploy
You can wrap it around a profile, and run the mvn build with that profile The other reason being to use profile is you can use this profile only whenever you need to generate the java classes, othertimes you can just run the regular build.
The format is
<profiles>
<profile>
<id>generateFromSchemas</id>
<plugin>
......
</plugin>
</profile>
<profiles>
mvn -P generateFromSchemas