Spring 优雅的流转状态数据

public enum OrderStatus {
    CREATED, PROCESSING, SHIPPED, DELIVERED, CANCELED
}

public enum OrderEvent {
    PAYMENT_RECEIVED, PROCESSING_COMPLETE, ITEM_SHIPPED, DELIVERY_CONFIRMED, CANCEL_REQUESTED
}

@Configuration
@EnableStateMachine
public class OrderStateMachineConfig extends EnumStateMachineConfigurerAdapter<OrderStatus, OrderEvent> {
    
    @Override
    public void configure(StateMachineTransitionConfigurer<OrderStatus, OrderEvent> transitions) throws Exception {
        transitions
            .withExternal()
                .source(OrderStatus.CREATED)
                .target(OrderStatus.PROCESSING)
                .event(OrderEvent.PAYMENT_RECEIVED)
            .and()
            .withExternal()
                .source(OrderStatus.PROCESSING)
                .target(OrderStatus.SHIPPED)
                .event(OrderEvent.PROCESSING_COMPLETE)
            .and()
            .withExternal()
                .source(OrderStatus.SHIPPED)
                .target(OrderStatus.DELIVERED)
                .event(OrderEvent.ITEM_SHIPPED)
            .and()
            .withExternal()
                .source(OrderStatus.DELIVERED)
                .target(OrderStatus.CANCELED)
                .event(OrderEvent.CANCEL_REQUESTED);
    }
    
    @Override
    public void configure(StateMachineConfigurationConfigurer<OrderStatus, OrderEvent> config) throws Exception {
        config
            .withConfiguration()
                .autoStartup(true);
    }
    
    @Override
    public void configure(StateMachineStateConfigurer<OrderStatus, OrderEvent> states) throws Exception {
        states
            .withStates()
                .initial(OrderStatus.CREATED)
                .states(EnumSet.allOf(OrderStatus.class));
    }
}