Drools already provides some functionality to define the order in which rules should be executed, like salience, activation groups, etc. When dealing with (possibly a lot of) large rule-sets, managing the order in which rules are evaluated might become complex. Ruleflow allows you to specify the order in which rule sets should be evaluated by using a flow chart. This allows you to define which rule sets should be evaluated in sequence or in parallel, to specify conditions under which rule sets should be evaluated, etc. This chapter contains a few ruleflow examples.
A rule flow is a graphical description of a sequence of steps that the rule engine needs to take, where the order is important. The ruleflow can also deal with conditional branching, parallelism, synchonization, etc.
To use a ruleflow to describe the order in which rules should be evaluatied, you should first group rules into rulefow-groups using the ruleflow-group rule attribute ("options" in the GUI). Then you should create a ruleflow graph (which is a flow chart) that graphically describe the order in which the rules should be considered (by specifying the order in which the ruleflow-groups should be evaluated).
rule 'YourRule' ruleflow-group 'group1' when ... then ... end
This rule will then be placed in the ruleflow-group called "group1".