JBossFuse:karaf@root> features:install camel-spark-rest 
Error executing command: Can not resolve feature:
Unsatisfied requirement(s):
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   package:(&(package=sun.reflect))
      sparkjava
   package:(&(package=spark.route)(version>=2.5.0)(!(version>=3.0.0)))
      camel-spark-rest
   package:(&(package=spark)(version>=2.5.0)(!(version>=3.0.0)))
      camel-spark-rest

JBossFuse:karaf@root> features:info camel-spark-rest
Description of camel-spark-rest 2.17.0.redhat-630237 feature
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Java 8 is needed for this feature to work and you need to add sun.reflect in the JDK 8 section of etc/jre.properties file