Keystore is created after writing secret key into it. So instead of "write alias" operation it is more "write alias and create backed keystore if not exists yet" operation.

How to reproduce:

• create credential store from scratch

  [standalone@localhost:9990 /] /subsystem=elytron/credential-store=myCredStore:add(uri="cr-store://test/myCredStore.jceks?create=true",  credential-reference={clear-text=pass123}, relative-to=jboss.server.config.dir)
  {"outcome" => "success"}
  

• myCredStore.jceks does not exists on FS (I would expect it will be created)

[standalone@localhost:9990 /] /subsystem=elytron/credential-store=myCredStore/alias=myAlias:add(secret-value=secret)
{"outcome" => "success"}

• myCredStore.jceks exists on FS

Setting high priority as lack of this behaviour can lead to more complex problems in multiprocess scenarios (e.g domain mode)