Hi, A recap of the problem i am trying to solve below:
Java accessibility requires accessibility provider classes to be present in the application classpath. In Java 8 accessibility provider jar was added to the "lib/ext" directory and the accessibility provider was added to the boot classpath. Some Linux distributions carried a patch that modified the boot classpath for Java 11 and up to include a predefined accessibility provider. Updating the boot classpath was a security risk and did not allow for alternative implementations of the accessibility provider that are configurable system-wide. Since Java runtime attempts to load accessibility using the application's classpath, a user has to modify each application's classpath to enable accessibility. This is a bad user experience. Sometimes it is not possible, e.g. the application files are immutable. Accessibility provider classpath can be specified in a new additional property in accessibility.properties. The older versions of JDK will ignore it and the change will not break an existing functionality. I have prepared a prototype[1] and was wondering if it would be ok to raise an enhancement issue and implement it. Best Regards, Vladimir. [1] https://github.com/openjdk/jdk/compare/master...vpa1977:jdk:accessibility_proto On Thu, Sep 21, 2023 at 10:21 AM Samuel Thibault <samuel.thiba...@ens-lyon.org> wrote: > > Vladimir Petko, le jeu. 21 sept. 2023 10:11:38 +1200, a ecrit: > > Samuel, please correct me if I'm wrong. The requirement is for the > > per-user (or system-wide) enablement of accessibility. The > > per-application setup is a bad user experience, and it would be nice > > to have a single point - properties file - that enables it. > > Yes, that's it. > > It is meaningless to enable accessibility only for some applicatins: > either the user needs it for all applications, or they don't need it at > all. > > Samuel > > > Java 8 achieves this by putting the accessibility provider jar in the > > 'ext' directory. Java 11 and up requires including an accessibility > > provider in the modules files. > > > > Any updates and fixes to the accessibility provider will require new > > releases of the openjdk package in Debian and Ubuntu. Adding > > accessibility providers to the build dependencies of the openjdk > > package also creates a circular build dependency that might introduce > > issues requiring careful synchronization between releases. > > > > I propose to add a new property 'java.accessibility.module_path'. The > > property will contain the list of locations of accessibility modules. > > Toolkit will construct the classloader using this path and the system > > class loader as a parent. Older releases will ignore this property. > > > > This feature will allow installation of the accessibility provider > > separate from the openjdk package and will satisfy the requirement of > > per-user and system-wide enablement of the accessibility provider. > > > > Best Regards, > > Vladimir. > > > > On Thu, Sep 21, 2023 at 9:48 AM Philip Race <philip.r...@oracle.com> wrote: > > > > > > Can you explain your need for this (a lot) better ? > > > > > > The location and loading is specified to be done by > > > java.util.ServiceLoader. > > > Whilst this might be possible by some enhanced syntax, which if present > > > invokes ServiceLoader specifying a ClassLoader for this jar file, it > > > would clearly be new API and only for future releases. > > > NB it would also be fiddly to implement as the value of the property is > > > a list of class names and > > > you can't add jar names to that without breaking older JDKs and > > > so you'd need some way to match new lines referencing the JAR file for > > > each class .. > > > > > > And likely we'd want to have new APIs like this - if they make sense - to > > > be focused on a module, not a jar, but building a runtime image from > > > modules using jlink is a normal thing to do, so I'm not sure what such > > > an API would look like and seems to be not what you want. > > > > > > I also don't understand the use case / problem. > > > Whatever launches your application can set > > > -Djavax.accessibility.assistive_technologies=<..> > > > and set the -cp to include your jar and you don't need to do anything > > > to the runtime image. > > > > > > -phil > > > > > > On 9/20/23 1:33 PM, Vladimir Petko wrote: > > > > Hi, > > > > > > > > Java accessibility.properties (.accessibility.properties) allows > > > > setting the class name of the accessibility provider but not the jar > > > > file containing it. > > > > > > > > Was there any consideration that prevents this feature from being > > > > implemented, such as security? > > > > > > > > It would be nice to have it implemented to allow system-wide/per-user > > > > configuration of the accessibility provider without rebuilding the > > > > runtime image. > > > > > > > > If this is something acceptable, I am happy to create an enhancement > > > > issue and work on it. > > > > > > > > Best Regards, > > > > Vladimir. > > > > > > > -- > Samuel > --- > Pour une évaluation indépendante, transparente et rigoureuse ! > Je soutiens la Commission d'Évaluation de l'Inria.
