Generate html report from jacoco agent inside a docker container

Question

I have a Dockerfile and run a spring boto application with jacoco agent inside a container

COPY jacocoagent.jar ./jacocoagent.jar

ENTRYPOINT ["java", "-javaagent:jacocoagent.jar=port=36320,destfile=jacoco-it.exec,output=tcpserver","-Dspring.profiles.active=local", "-jar", "app.jar"]

After that I run

java -jar jacococli.jar report build/jacoco/jacoco-it.exec --classfiles build/classes --sourcefiles src/main/java/ --html build/reports/jacoco/endToEndTetsReport

to generate jacoco-it.exec. Then I want to generate html file by jacococli,

java -jar jacococli.jar report build/jacoco/jacoco-it.exec --classfiles build/classes --sourcefiles src/main/java/ --html build/reports/jacoco/endToEndTetsReport

But the problem is for jacococli, it need a classfiles but I only use .jar file here. So how do I gernare a html report without classfiles or how I get the classfiles from .jar file?