接口分层结构
- com.budwk.app.flow.engine.Action
- com.budwk.app.flow.engine.AssignmentHandler
- com.budwk.app.flow.engine.CandidateHandler
- com.budwk.app.flow.engine.Context
- com.budwk.app.flow.engine.DecisionHandler
- com.budwk.app.flow.engine.FlowEngine
- com.budwk.app.flow.engine.FlowInterceptor