如何与Vaadin4Spring EventBus一起使用新的Vaadin4Spring

Question

Vaadin团队目前发布了一个addon，据我所知，它是基于非官方的Vaadin4Spring加载项：

Vaadin：https://vaadin.com/directory#addon/vaadin-spring-boot

Vaadin4Spring：https://github.com/peholmst/vaadin4spring

请注意！截至2015年2月，Vaadin正在开发一个正式的Spring附加组件--它将是Vaadin4Spring的一小部分。一旦正式外接程序发布，Vaadin4Spring将被转换成一组附加组件，这些插件提供了官方插件没有的特性。您可以在这里跟踪官方附加程序的进展：https://github.com/vaadin/spring。

但是，Vaadin4Spring缺少了一些Vaadin4Spring拥有的很酷的特性(如Vaadin4Spring的作者Petter m在上面提到的)，比如EventBus框架，这是非常有用的。

现在，我已经设置了一个包含Vaadin4Spring和Vaadin4Spring addon的Maven项目：

    <!-- Vaadin Spring Boot -->
    <dependency>
        <groupId>com.vaadin</groupId>
        <artifactId>vaadin-spring-boot</artifactId>
        <version>${vaadin.spring.boot.version}</version>
    </dependency>

基本上，我希望使用这两个框架的特性(或者更好的是，我希望使用Vaadin Spring Boot作为主要框架，并与它一起使用Vaadin4Spring EventBus特性)。然而，我注意到的问题是，这两个框架似乎还不能共存。

如果像上面一样添加这两个加载项，当我运行应用程序时，不会发现任何视图和UI(在日志下面显示了我的意思)：

2015-03-01 22:07:22.001... SpringViewProvider: Looking up VaadinViews 
2015-03-01 22:07:22.006  WARN SpringViewProvider: No VaadinViews found ... 
...
2015-03-01 22:12:12.584  INFO: Checking the application context for Vaadin UIs 
2015-03-01 22:12:12.594  WARN: Found no Vaadin UIs in the application context

但是视图和UI确实存在！它们由Vaadin Spring Boot插件管理(以下是一些示例代码)：

UI：

@SpringUI("")
@Theme("valo")
public class DemoUI extends UI {

    private static final long serialVersionUID = 193481619798227053L;

    @Autowired
    private Greeter greeter;

    @Autowired
    private ApplicationContext applicationContext;

    private final SpringViewProvider viewProvider;

    private VerticalLayout layout;

    @Autowired
    public DemoUI(SpringViewProvider viewProvider) {
        this.viewProvider = viewProvider;
    }

    @Override
    protected void init(VaadinRequest request) {        
        layout = new VerticalLayout();
        layout.setMargin(true);
        layout.setSpacing(true);
        setContent(layout);

        Label greetings = new Label(greeter.getGreeting());
        layout.addComponent(greetings);

        final CssLayout navigationBar = new CssLayout();
        navigationBar.addStyleName(ValoTheme.LAYOUT_COMPONENT_GROUP);
        navigationBar.addComponent(createNavigationButton("View Scoped View", ViewScopedView.VIEW_NAME));
        navigationBar.addComponent(createNavigationButton("UI Scoped View", UIScopedView.VIEW_NAME));
        navigationBar.addComponent(createNavigationButton("Another UI Scoped View", AnotherUIScopedView.VIEW_NAME));
        layout.addComponent(navigationBar);     

        final Panel viewContainer = new Panel();
        viewContainer.setSizeFull();
        layout.addComponent(viewContainer);
        layout.setExpandRatio(viewContainer, 1.0f);

        Navigator navigator = new Navigator(this, viewContainer);
        navigator.addProvider(viewProvider);



    }

    private Button createNavigationButton(String caption, String viewName) {
        Button button = new Button(caption);
        button.addStyleName(ValoTheme.BUTTON_SMALL);
        button.addClickListener(event -> { 
            try {
                getUI().getNavigator().navigateTo(viewName);
            }
            catch (IllegalArgumentException e) {
                // view with the given name is not mapped
                System.out.println("Not mapped view with name: " + viewName);
            }
        });
        return button;
    }

}

带有@SpringView注释的视图：

@SpringView(DefaultView.VIEW_NAME)
public class DefaultView extends VerticalLayout implements View {

    private static final long serialVersionUID = -2052937117362922764L;

    public static final String VIEW_NAME = "";

    @Override
    public void enter(ViewChangeEvent event) {
         // the view is constructed in the init() method()      
    }

    @PostConstruct
    void init() {
        addComponent(new Label("This is the default view"));
    }

}

其他观点也是如此。当从pom.xml中移除这两个依赖项时，一切都正常：

    <!-- Vaadin4Spring addon, the EventBus framework needs this addon -->
    <dependency>
        <groupId>org.vaadin.spring</groupId>
        <artifactId>spring-boot-vaadin</artifactId>
        <version>0.0.5-SNAPSHOT</version>
    </dependency>
    <!-- Vaadin4Spring EventBus feature I would like to use with Vaadin Spring Boot -->
    <dependency>
        <groupId>org.vaadin.spring</groupId>
        <artifactId>spring-vaadin-eventbus</artifactId>
        <version>0.0.5-SNAPSHOT</version>
    </dependency>

不允许我使用EventBus框架。是否有人已经探索过这个新的词条，也有同样的需要？你知道如何把这两个世界结合起来吗？或者，将Vaadin4Spring工具用于Vaadin4Spring还为时尚早，我们应该等待将Vaadin4Spring特性转换为一组将完成Vaadin Spring Boot的加载项，就像我在发布的第一个块中所说的那样？

编辑:我还试图在Spring应用程序类中添加一个@ComponentScan注释，同时将三个依赖项放在一起，但没有帮助.

如果我添加spring-vaadin而不是spring-boot-vaadin

        <!-- Vaadin4Spring -->
        <dependency>
            <groupId>org.vaadin.spring</groupId>
            <artifactId>spring-vaadin</artifactId>
            <version>${vaadin4spring.version}</version>
        </dependency>
        <!-- Vaadin4Spring EventBus framework -->
        <dependency>
            <groupId>org.vaadin.spring</groupId>
            <artifactId>spring-vaadin-eventbus</artifactId>
            <version>${vaadin4spring.version}</version>
        </dependency>

视图和UI被加载，我可以在浏览器中看到它们，但只要我想开始使用事件总线，就会得到以下异常：

org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'vaadinSpringBootDemoApplication': Injection of autowired dependencies failed; nested exception is org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.vaadin.spring.events.EventBus$ApplicationEventBus demo.VaadinSpringBootDemoApplication.applicationEventBus; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.vaadin.spring.events.EventBus$ApplicationEventBus] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:334)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1202)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:476)
    at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:303)
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:230)
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:299)
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:194)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:762)
    at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:757)
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:480)
    at org.springframework.boot.context.embedded.EmbeddedWebApplicationContext.refresh(EmbeddedWebApplicationContext.java:118)
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:691)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:321)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:961)
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:950)
    at demo.VaadinSpringBootDemoApplication.main(VaadinSpringBootDemoApplication.java:21)
Caused by: org.springframework.beans.factory.BeanCreationException: Could not autowire field: private org.vaadin.spring.events.EventBus$ApplicationEventBus demo.VaadinSpringBootDemoApplication.applicationEventBus; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.vaadin.spring.events.EventBus$ApplicationEventBus] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:561)
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:88)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessPropertyValues(AutowiredAnnotationBeanPostProcessor.java:331)
    ... 16 common frames omitted
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type [org.vaadin.spring.events.EventBus$ApplicationEventBus] found for dependency: expected at least 1 bean which qualifies as autowire candidate for this dependency. Dependency annotations: {@org.springframework.beans.factory.annotation.Autowired(required=true)}
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoSuchBeanDefinitionException(DefaultListableBeanFactory.java:1308)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1054)
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:949)
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredFieldElement.inject(AutowiredAnnotationBeanPostProcessor.java:533)
    ... 18 common frames omitted

看来EventBus.* bean没有在Spring IoC容器中注册。该怎么办呢？

Answer 1

问题是VaadinSessionScope尚未在官方spring4vaadin中实现。您需要创建一个非官方的spring4vaadin。

你的pom档案：

<!-- Official Vaadin4Spring -->
<dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-spring</artifactId>
    <version>${vaadin.spring.version}</version>
</dependency>
    <dependency>
    <groupId>com.vaadin</groupId>
    <artifactId>vaadin-spring-boot</artifactId>
    <version>${vaadin.spring.boot.version}</version>
</dependency>
<!-- Unofficial Vaadin4Spring -->
<dependency>
    <groupId>org.vaadin.spring</groupId>
    <artifactId>spring-vaadin</artifactId>
    <version>${vaadin4spring.version}</version>
</dependency>
<!-- Vaadin4Spring EventBus Addon -->
<dependency>
    <groupId>org.vaadin.spring</groupId>
    <artifactId>spring-vaadin-eventbus</artifactId>
    <version>${vaadin4spring.version}</version>
</dependency>

UI示例：

@SpringUI("/ui")
@Title("Test")
@Theme("valo")
public class MainUI extends UI {

    private final Logger log = LoggerFactory.getLogger(MainUI.class);

    @Inject
    EventBus.UIEventBus eventBus;

    @Override
    protected void init(VaadinRequest request) {
        eventBus.subscribe(this);

        setContent(new Button("Create event", (e) -> {
            eventBus.publish(EventScope.UI, "Payload string.");
        }));
    }

    @EventBusListenerMethod
    public void onEvent(String str) {
        log.debug("Event received: {}", str);
    }
}

应用主类

@Configuration
@ComponentScan
@EnableAutoConfiguration
@EnableVaadinEventBus
public class Application {

    private static final Logger log = LoggerFactory.getLogger(Application.class);

    @Bean
    static VaadinSessionScope vaadinSessionScope() {
        return new VaadinSessionScope();
    }

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

Answer 2

我想你可以两者兼得。尝试包含"org.vaadin.spring:spring-vaadin:0.0.5-SNAPSHOT"，因为VaadinEventbusConfiguration依赖于内部类。

为什么需要包括"org.vaadin.spring:spring-boot-vaadin:0.0.5-SNAPSHOT"？如果您真的需要它，请尝试从@EnableAutoConfiguration中排除org.vaadin.spring.boot.VaadinAutoConfiguration。

编辑:您可以在这个分支中获得带有正式spring4vaadin的加载项：support

Answer 3

作为对已接受的答案的更新:非官方的vaadin4spring插件的模块被重命名了。现在我们必须添加这个依赖项：

<dependency>
    <groupId>org.vaadin.spring.extensions</groupId>
    <artifactId>vaadin-spring-ext-core</artifactId>
    <version>${vaadin4spring.version}</version>
</dependency>