Recently, I found Sail4J library GitHub - renliangfeng/sail4j-iiq-idn which provides a way to build Java Class in your IDE (I use VSCode) to beanshell code and generates rule XML. It is another way to generate your large rule libraries with Unit testing and No compilation errors.
I used the Sail4J libraries to create a Java Code that generates the rule XMLs from the Java Class(es) you create using the Sail4J annotations and use the apache velocity to create Rule XML.
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