There’s no way to hide Flow service source code. After all, it is XML underneath. i.e. no compilation.
The only way is to assign a new ACL to the folders and services for READ ACL. However, anyone who creates exact same ACL and assigns to their user ID will be able to view it. This is same for all internal wM services.
As for Java services, delete all *.java, *.frag and *.idf files in the packages.
Philip
#Integration-Server-and-ESB#Flow-and-Java-services#webMethods