java - Spring Boot - 在事件发布时导致 bean 重新创建的原型范围

Question

我正在开发一个依赖于原型范围内的某些 bean 的应用程序，因为它们在调用时需要从头开始重新创建。这些 bean 基本上是选项卡窗格中的 3 个选项卡：ExpenseTab、IncomeTab 和 BudgetTab。应用程序使用一个事件 BudgetUpdateEvent，每次 ExpenseTab 或 IncomeTab 发生变化时都会触发该事件，BudgetTab 会像这样监听它：

@Override
public void onApplicationEvent(BudgetUpdateEvent event) 
{
    budgetCalculator.calculateBalance();

    showEntities();
}

BudgetTab bean 注释如下：

@Component
@Scope(ConfigurableBeanFactory.SCOPE_PROTOTYPE)
@Lazy
public class BudgetTab extends EntityTab<BudgetEntry> implements 
ApplicationListener<BudgetUpdateEvent>
{
    //...
}

我通过将 TabPane 对象传递给构造函数来调用这些 bean，如下所示：

budgetTab = springContext.getBean(BudgetTab.class, tabPane, budgetEntryRepo.findAll());

TabPane 对象不是也不能是 Bean。这对于了解问题所在很重要。

当我从 ExpenseTab 中触发事件时，我按如下方式执行：

@Autowired
private ApplicationEventPublisher publisher;

publisher.publishEvent(new BudgetUpdateEvent(this));

出于某种原因，如果 BudgetTab 被标记为原型范围，则在发布此事件时会出现异常，这表明 Spring 正在重新创建此 bean 的新实例：

Exception in thread "JavaFX Application Thread" org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'budgetTab' defined in file [C:\Users\607337\Documents\EclipseProjects\Budget\target\classes\com\mdenis\budget\components\tabs\BudgetTab.class]: Unsatisfied dependency expressed through constructor parameter 0; nested exception is org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'javafx.scene.control.TabPane' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:769)
at org.springframework.beans.factory.support.ConstructorResolver.autowireConstructor(ConstructorResolver.java:218)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.autowireConstructor(AbstractAutowireCapableBeanFactory.java:1341)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1187)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555)
at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515)
at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:338)
at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:204)
at org.springframework.context.event.AbstractApplicationEventMulticaster.retrieveApplicationListeners(AbstractApplicationEventMulticaster.java:239)
at org.springframework.context.event.AbstractApplicationEventMulticaster.getApplicationListeners(AbstractApplicationEventMulticaster.java:196)
at org.springframework.context.event.SimpleApplicationEventMulticaster.multicastEvent(SimpleApplicationEventMulticaster.java:134)
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:402)
at org.springframework.context.support.AbstractApplicationContext.publishEvent(AbstractApplicationContext.java:359)
at com.mdenis.budget.components.tabs.ExpenseTab.deleteEntity(ExpenseTab.java:107)
at com.mdenis.budget.components.tabs.EntityTab.lambda$initButtons$4(EntityTab.java:235)
at javafx.base/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86)
at javafx.base/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at javafx.base/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at javafx.base/com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at javafx.base/com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49)
at javafx.base/javafx.event.Event.fireEvent(Event.java:198)
at javafx.graphics/javafx.scene.Node.fireEvent(Node.java:8879)
at javafx.controls/javafx.scene.control.Button.fire(Button.java:200)
at javafx.controls/com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:206)
at javafx.controls/com.sun.javafx.scene.control.inputmap.InputMap.handle(InputMap.java:274)
at javafx.base/com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218)
at javafx.base/com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80)
at javafx.base/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238)
at javafx.base/com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191)
at javafx.base/com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56)
at javafx.base/com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114)
at javafx.base/com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74)
at javafx.base/com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54)
at javafx.base/javafx.event.Event.fireEvent(Event.java:198)
at javafx.graphics/javafx.scene.Scene$MouseHandler.process(Scene.java:3851)
at javafx.graphics/javafx.scene.Scene$MouseHandler.access$1200(Scene.java:3579)
at javafx.graphics/javafx.scene.Scene.processMouseEvent(Scene.java:1849)
at javafx.graphics/javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2588)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:397)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:295)
at java.base/java.security.AccessController.doPrivileged(Native Method)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$2(GlassViewEventHandler.java:434)
at javafx.graphics/com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:390)
at javafx.graphics/com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:433)
at javafx.graphics/com.sun.glass.ui.View.handleMouseEvent(View.java:556)
at javafx.graphics/com.sun.glass.ui.View.notifyMouse(View.java:942)
at javafx.graphics/com.sun.glass.ui.win.WinApplication._runLoop(Native Method)
at javafx.graphics/com.sun.glass.ui.win.WinApplication.lambda$runLoop$3(WinApplication.java:174)
at java.base/java.lang.Thread.run(Thread.java:834)
Caused by: org.springframework.beans.factory.NoSuchBeanDefinitionException: No qualifying bean of type 'javafx.scene.control.TabPane' available: expected at least 1 bean which qualifies as autowire candidate. Dependency annotations: {}
at org.springframework.beans.factory.support.DefaultListableBeanFactory.raiseNoMatchingBeanFound(DefaultListableBeanFactory.java:1658)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1217)
at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171)
at org.springframework.beans.factory.support.ConstructorResolver.resolveAutowiredArgument(ConstructorResolver.java:857)
at org.springframework.beans.factory.support.ConstructorResolver.createArgumentArray(ConstructorResolver.java:760)

当我删除原型范围时，此行为停止并且 BudgetTab 正确更新，但随后我需要该 bean 其他方面的原型范围才能正常工作。

底线是：为什么 Spring 在触发所述 bean 侦听的事件时重新实例化原型范围的 bean？

标签： javaspring-booteventspublish