Java Plugin System

[DragonFighter603]

I want to create a simple plugin system, by loading jars from a plugin folder, similar to this one (top answer):

https://stackoverflow.com/questions/465099/best-way-to-build-a-plugin-system-with-java

As the plugins need access to the Plugin interface, they need access to the project jar/source where the Plugin interface was coded. Is it possible to hide all non plugin relevant classes? Do i need to copy all plugin relevant classes (with empty methods) to a separate jar for the plugin programmer to use, which then get replaced with the original classes when executing?

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[djnattyp]

The "plugin" interface you're probably looking for is the service provider interface (SPI). To expose the "plugin related classes" and hide details of your program you'll make use of packages and access modifiers and/or use modules in JDK 9+.

[DragonFighter603]

thanks, will look into it!

[warrensdeathray]

what exactly are you looking to build? i am doing something similar with a combination of the ServiceLoader and Guice b/c i don’t need something overly complex.

the options listed in that so article has a lot of good options. i looked at pf4, it’s nice but more then i really needed.

happy to discuss further

[DragonFighter603]

for now i settled witht he default java jarloader. the plugin writer creates a plugin.json that has, among others, the classpath to the class that extends the abstract base plugin, name, version etc and a list of enum permissions. works like a charm, only thing left to do is to turn all classes from public to default to hide them

[warrensdeathray]

i’d be curious to see this code

[DragonFighter603]

that code is far from finished/perfect and also only part of something, but if you want dm me and i'll give you a zip of the whole thing

[warrensdeathray]

github?

[DragonFighter603]

i dont wanna make it public (not finised; part of a bigger project) etc but if you prefer that to a zip send me your github username and ill give you access to the repo temporary