Spring 状态机 bean 检测不起作用

Question

我目前正在使用 Spring 状态机构建一个小示例项目。

我的配置：

@Configuration
@EnableStateMachine
public class StateMachineConfiguration extends EnumStateMachineConfigurerAdapter<States, Events> {

    @Override
    public void configure(StateMachineStateConfigurer<States, Events> states)
            throws Exception {
        states
                .withStates()
                .initial(States.LOCKED)
                .states(EnumSet.allOf(States.class));
    }

    @Override
    public void configure(StateMachineTransitionConfigurer<States, Events> transitions)
            throws Exception {
        transitions
                .withExternal()
                .source(States.LOCKED)
                .target(States.UNLOCKED)
                .event(Events.COIN)
                .and()
                .withExternal()
                .source(States.UNLOCKED)
                .target(States.LOCKED)
                .event(Events.PUSH);
    }

    @Bean
    public StateMachineListener<States, Events> listener() {
        return new StateMachineListenerAdapter<States, Events>() {
            @Override
            public void stateChanged(State<States, Events> from, State<States, Events> to) {
                System.out.println("State change to " + to.getId());
            }
        };
    }
}

当我现在尝试注入状态机时

@Autowired
StateMachine<States, Events> stateMachine;

IntelliJ 给了我提示，这不能自动连接，因为那里没有 bean。如果我运行应用程序，我也会遇到异常。

梯度依赖：

compile 'org.springframework.statemachine:spring-statemachine-core:2.0.1.
compile group: 'org.springframework.boot', name: 'spring-boot-starter', version: '2.0.1.RELEASE'
compile group: 'org.springframework.shell', name: 'spring-shell-starter', version: '2.0.1.RELEASE'
compile group: 'org.springframework.statemachine', name: 'spring-statemachine-boot', version: '1.2.11.RELEASE'

Answer 1

我不知道问题是什么..但以下代码片段对我有用。

@Configuration
@EnableStateMachine
public class StateMachineConfiguration {

    private final Logger logger = LoggerFactory.getLogger(this.getClass());

    @Bean
    public StateMachine<States, Events> stateMachine(StateMachineListener<States, Events> listener) throws Exception {
        StateMachineBuilder.Builder<States, Events> builder = StateMachineBuilder.builder();

        builder.configureStates()
            .withStates()
            .initial(States.LOCKED)
            .states(EnumSet.allOf(States.class));

        builder.configureTransitions()
            .withExternal()
            .source(States.LOCKED)
            .target(States.UNLOCKED)
            .event(Events.COIN)
            .and()
            .withExternal()
            .source(States.UNLOCKED)
            .target(States.LOCKED)
            .event(Events.PUSH);

        StateMachine<States, Events> stateMachine = builder.build();
        stateMachine.addStateListener(listener);
        return stateMachine;
    }

    @Bean
    public StateMachineListener<States, Events> listener() {
        return new StateMachineListenerAdapter<States, Events>() {
            @Override
            public void stateChanged(State<States, Events> from, State<States, Events> to) {
                logger.info("State change to " + to.getId());
            }
        };
    }
}