Here are a few good rule engines for easy learning
drools
Very powerful brms system, and the ecology is also very good, the problem is that it is complicated to use, refer to https://github.com/kiegroup/drools && https://www.drools.org/
OpenL Tablets
Refer to https://github.com/openl-tablets/openl-tablets , there are not many domestic materials, but the official documentation is still very good
Easy Rules
The official introduction, a fool-style rule engine based on pojo, is simple to use, but also relatively powerful, supports rule processing in the bdd mode, is very friendly to the integration of the java system,
simple to use, and supports file-based rule loading. It is extensible and can add its own processing based on db and s3 mode. The built-in Listener is also
a very good monitoring point, which is convenient for us to conduct rule audit storage
RuleBook
The rule engine based on java8 lambda mode is also more flexible in use, reference material https://github.com/deliveredtechnologies/rulebook
Explanation
If the drools, Easy Rules, openl-tablets are more flexible from the configurable management (support configuration changes, with the ability to script)