一个轻量实用的Java状态机框架--Cola-StateMachine

Cola-StateMachine是一个轻量级的实用Java状态机框架，它可以帮助开发者在Java应用中实现状态机逻辑。以下是一个简单的使用示例：

import com.alibaba.cola.statemachine.StateMachine;
import com.alibaba.cola.statemachine.StateMachineBuilder;
import com.alibaba.cola.statemachine.StateMachineModel;
 
public class OrderStateMachine {
 
    public enum OrderStatus {
        NEW,
        PAID,
        DELIVERED,
        RETURNED,
        CLOSED
    }
 
    public enum OrderEvent {
        PAY,
        DELIVER,
        RETURN
    }
 
    public static void main(String[] args) {
        StateMachineModel model = StateMachineModel.builder()
                .source(OrderStatus.NEW)
                .target(OrderStatus.PAID)
                .event(OrderEvent.PAY)
                .build();
 
        StateMachineModel model2 = StateMachineModel.builder()
                .source(OrderStatus.PAID)
                .target(OrderStatus.DELIVERED)
                .event(OrderEvent.DELIVER)
                .build();
 
        StateMachineModel model3 = StateMachineModel.builder()
                .source(OrderStatus.DELIVERED)
                .target(OrderStatus.CLOSED)
                .event(OrderEvent.RETURN)
                .build();
 
        StateMachine<OrderStatus, OrderEvent> stateMachine = StateMachineBuilder.builder()
                .models(model, model2, model3)
                .build();
 
        OrderStatus currentStatus = OrderStatus.NEW;
        OrderEvent event = stateMachine.fireEvent(currentStatus, OrderEvent.PAY);
 
        System.out.println("Event: " + event + ", new status: " + stateMachine.fireEvent(currentStatus, OrderEvent.PAY));
    }
}

这个例子定义了一个订单状态机，包括订单的状态和事件。然后使用StateMachineBuilder来构建状态机，并通过fireEvent方法触发状态转换。这个简单的例子展示了如何使用Cola-StateMachine来管理和转换状态，是一个很好的入门示例。