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Grouper rules are configurable declarative scripts which run at certain times and perform actions on the registry. They are similar to hooks though you don't have to write Java, and it does not require a change to a config file to enable a rule (i.e. anyone with authority in the folder hierarchy could enable a rule). This is similar to JBoss drools. There is no heuristic to find the best rule, it finds all matching rules to fire. Rules are unordered. Some rule "Then" clauses could kick off more rules.
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