4.0.0 io.zipkin.zipkin2 zipkin-collector-parent 3.4.0 zipkin-collector Collector: Core Library ${project.basedir}/../.. org.slf4j slf4j-api ${slf4j.version} com.github.valfirst slf4j-test 3.0.1 test maven-surefire-plugin org.slf4j:slf4j-simple