I think you will need a link to the PDF as attachments are stripped from the ML
On Tue 19 Sep 2017 at 19:57, Robert Scholte <rfscho...@apache.org> wrote: > Attached a single page overview. > > Per block you'll see in the upper left corner the executed plugin > The left column contains the extensions and plugin in orderas specified in > the pom.xml > In every classloadercolumn you'll see numbers which represent the order. > > I hope I didn't make any mistakes. > Tomorrow I have enough time to see if I understand what's happening here. > > I will come back with my conclusions. > > Robert > > On Tue, 19 Sep 2017 06:55:08 +0200, Igor Fedorenko <i...@ifedorenko.com> > wrote: > > > TL;DR your test project exposed two existing bugs, one change in > > behaviour and one quirk I can't explain > > > > * Build `<extensions>` are loaded by two classloaders, which is a bug in > > DefaultProjectBuildingHelper#createProjectRealm and explains why you see > > extjar1/extjar2 in the output > > * ClassRealm does not allow same foreign-import from multiple > > classloaders, which is a bug and explains why it is not possible to load > > same resource from multiple plugins/extensions > > * TCCL does not have access to private (i.e. not exported) resources of > > this extensions plugin, which is a change of behaviour introduced by > > mng-6209 fix > > * Also, component injection order appears to be backwards, but maybe > > Stuart can explain why. > > > > > > Below is more detailed explanation of expected and observed behaviour > > > > > > ## Component injection depends on the currently running plugin and the > > injection site > > > > Currently running plugins have access to the following component > > implementations: > > > > * Regular plugin has access to components implemented by the plugin, > > project build extensions, if any (via project class realm foreign > > import) and Maven Core. > > * Extension plugin has access to components implemented by the project > > build extensions and Maven Core. > > * Without a running plugin (e.g., during project dependency resolution), > > components implemented by the project build extensions and Maven Core > > are accessible. > > > > Different injection sites have access to the following component > > interfaces: > > > > * Maven Core has access to component interfaces defined by the core > > itself (obviously) > > * Project build extensions have access to **public** component > > interfaces defined by Maven Core and component interfaces defined by the > > build extension itself (there is no way to access component interfaces > > defined in other extensions) > > * Regular plugins have access to **public** component interfaces defined > > by Maven Core, component interfaces **exported** by build extensions and > > component interfaces defined in the plugin itself > > > > For injection to work, injection site has to have access to the > > component interface and the component implementation must be accessible > > through the current context. > > > > From what I can tell, in your example all plugins have access to the > > right components when using current 3.5.2-SNAPSHOT. The injection order > > does appear to be backwards from what I expected, however. > > > > > > ## Resources lookup fully depends on classpath visibility, specifically > > > > * Regular plugin class realm has access to resources from the plugin > > itself, from **exported** packages of the project build extensions and > > **public** Maven Core packages > > * Extensions plugin class realm has access to the resources from the > > extensions plugin itself and from **public** Maven Core packages > > * Project class realm has access to classes and resources **exported** > > by project build extensions and **public** Maven Core packages > > > > I see three problems here > > > > * Maven adds build single-jar `<extensions>` elements directly to > > project class realm **and** creates separate extensions class realms for > > them. Which results in duplicate classes/resources loaded by two > > classloaders and explains why you see extjar1/extjar2 output (which you > > shouldn't according to the explanation above) > > * ClassRealm does not allow foreign-import of the same package from > > multiple classloaders. This makes it impossible to load the same > > resource from multiple plugins/extensions. > > * Extensions plugins cannot access their own private (i.e. not exported) > > resources via TCCL, this is change in behaviour introduced by mng-6209 > > fix > > > > Hope this helps > > --------------------------------------------------------------------- > To unsubscribe, e-mail: dev-unsubscr...@maven.apache.org > For additional commands, e-mail: dev-h...@maven.apache.org -- Sent from my phone
