Steps to recreate:

1. Set umask to 0027
2. Run git clone https://github.com/cloudfoundry/java-buildpack
3. Run bundle exec rake package OFFLINE=true version=v3.8
4. Run cf create-buildpack java_buildpack_test build/java-buildpack-offline-7a37ff3.zip 9 --enable
5. Run cf push spring-music -b java_buildpack_test.

Output:

Downloading java_buildpack_test...
Downloaded java_buildpack_test (264.1M)
Creating container
Successfully created container
Downloading app package...
Downloaded app package (21.1M)
Staging...
Failed to compile droplet
Exit status 223
Staging failed: Exited with status 223

Seems like a permissions issue on the bin/* scripts. Can the build pack build scripts force permissions to 755 for those scripts?