For a service, you can just turn on the audit logging, so you will know when the service is executed. (you can use client (including java) code to check audit log db so check when each service was called).
For if or not email sent out, you can cc to a mail box, or you create email service, so you can use standard audit logging method to tracking if it’s call.
for doc user status change, you can check doc status with API any time, but if you want to know when the status changed, you need to query the activity log for that.
Still, It doesn’t make much sense to use a stand alone java system to check all these. IS already made most of these info easily available.
hope i understand you correctly.
#webMethods#B2B-Integration#Integration-Server-and-ESB