Mike/Code Ranger, the obvious suggestion is to put your application
(including the "CORE module") in its own layer, rather than the boot layer.
Alex
On 1/13/2025 1:46 AM, Code Ranger wrote:
Hello, Alan
Thank you for your suggestions, help, and time. I truly appreciate and
am deeply grateful for them.
However, I’m afraid I failed to convey the most crucial point.
Therefore, I decided to illustrate it graphically. I believe everything
will become clear now.
Please, see https://ibb.co/bLTzp0n
If you have any questions, I’m ready to answer them, as I’ve already
mentioned, this matter is extremely important to me.
On 1/13/25 09:54, Alan Bateman wrote:
On 12/01/2025 09:12, Code Ranger wrote:
1. I see that JDK-8347283 was closed with your comment. I don't
agree with you decision, but I can be wrong. Let me explain, why I
think that is wrong using this concrete example.
Boot layer has jdk modules and main application modules. The CORE
module of the application creates plugins with child layers. No one
in the world can know what plugins will be created and used when the
main application starts. Now, somewhere in the future, the module A
from plugin X will require module B from boot layer to open its
package to module A. I believe, that the only solution to do it is to
provide the controller of the boot layer.
2. Now, I tried to do apiModule.addOpens in CORE module. I got:
java.lang.IllegalCallerException: com.foo.api.packagename is not open
to module com.foo.core
at java.base/java.lang.Module.addOpens(Module.java:918) ~[?:?]
Therefore, as far as I understand, for the solution you are
suggesting to work, the packagename package of the API module must be
opened to the Core module. But the main problem, as I've said above -
no one knows in advance which packages of which modules from the boot
layer will need to be opened/exported, etc., to the plugins that will
be created by users and deployed dynamically.
Your second mail reveals a bit more but it's not clear if your issue
is one of these scenarios:
1. A serialization library that is incompatible with strong
encapsulation. If so, that's a different discussion.
2. The API and CORE modules have some interesting internals that the
authors of these modules have chosen not to export. The author of a
plugin doesn't agree. As you've found, this can only be facilitated
with cooperation from code in CORE. It may additionally require CLI
option if API won't open its packages to CORE. This means running with
--add-opens API/com.foo.api=CORE so that CORE can open API's package
to the plugin module in the child layer.
3. A badly behaved plugin that depends on the internals of standard or
JDK modules. This would be whack-a-mole and require a combination of
CLI options and code in CORE to open java.* and jdk.* packages to the
offending code in the plugin.
-Alan
