Content interface Question

Hey Guys,

Im playing a bit with the content interface to reduce our snap size.

I’m create an provide snap like:

java-c-lib-share

with follow snapcraft.yaml

name: java-c-lib-share # you probably want to 'snapcraft register <name>'
version: '0.1' # just for humans, typically '1.2+git' or '1.3.2'
summary: Share all necessary libs and jre to use and easy upgrade
description: |
  Share all necessary libs and c libs to use it in all module projects

grade: stable # must be 'stable' to release into candidate/stable channels
confinement: strict # use 'strict' once you have the right plugs and slots


slots:
 java-share:
  interface: content
  content: java-c-share
  read:
   -  $SNAP/usr
parts:
 native:
  source: .
  plugin: dump
  organize:
   '*' : usr/

and in my consumer i create an small snapcraft like:

name: my-snap-name # you probably want to 'snapcraft register <name>'
version: '0.1' # just for humans, typically '1.2+git' or '1.3.2'
summary: Single-line elevator pitch for your amazing snap # 79 char long summary
description: |
  This is my-snap's description. You have a paragraph or two to tell the
  most important story about your snap. Keep it under 100 words though,
  we live in tweetspace and your description wants to look good in the snap
  store.

grade: stable # must be 'stable' to release into candidate/stable channels
confinement: strict # use 'strict' once you have the right plugs and slots
plugs:
 java-share:
   interface: content
   content: java-c-share
   target: $SNAP/usr
   default-provider: java-c-lib-share
parts:
  my-part:
    # See 'snapcraft plugins'
    plugin: nil

after then I did

snap connect my-snap-name:java-share java-c-lib-share:java-share

but I didn’t see the mounted interface in /snap/my-snap-name/x1

Did I something wrong?
I also tried with target: $SNAP_DATA/usr or $SNAP/share

any suggestions or hitpoint?

Greets

I have add now to the consumer snap an shell, but it still not mounting, I also use the example from here:
https://snapdocs.labix.org/the-content-interface/1074