春天不注入singleton bean控制器到另一个控制器

Question

我正在写一个应用程序，使用弹簧的依赖注入和gui的javafx。在春季配置中，我定义了所有的bean（DAO，服务和GUI控制器）。一切都很好。但是我现在遇到了一些麻烦。

在主机控制器中，我使用了一个叫做工具箱的服务。它被注入，我可以使用它很好。然而，当我想打开第二个窗口，它也使用相同的服务，它似乎并没有被注入。我不断收到nullpointerexceptions，告诉我toolBox为null。

我的弹簧配置为：

<bean id="TagListFrame" name="TagListFrame" class="TagListFrame" scope="singleton"> 
    <property name="toolBox" ref="ToolBoxService"/> 
</bean> 
<bean id="ToolBoxService" name="ToolBoxService" class="ToolBoxImpl" scope="singleton"> 
    <property name="tagDao" ref="JDBCTagDao"/> 
</bean> 
<bean id="JDBCTagDao" name="JDBCTagDao" class="JDBCTagDao" scope="singleton"> 
    <property name="connection" ref="HSQLDBConnection"/> 
</bean> 

在TagListFrame控制器

我定义的变量和用于它的装定。

如果我从mainframecontroller调用setter函数并使用它对工具箱的引用，它工作正常，但我似乎无法让它与spring一起工作。

我打开新的窗口，用下面的代码：

Scene newScene = new Scene(root, 400, 300); 
Stage newStage = new Stage(); 
newStage.setTitle("Window Title); 
newStage.initOwner(primaryStage); 
newStage.setScene(newScene); 
newStage.setX(primaryStage.getX() + 100); 
newStage.setY(primaryStage.getY() + 100); 
newStage.show(); 

堆栈跟踪：

Exception in thread "JavaFX Application Thread" java.lang.NullPointerException 
at at.ac.tuwien.sepm.ws13.qse01.service.PictureInfoShowImpl.getAllTags(PictureInfoShowImpl.java:226) 
at at.ac.tuwien.sepm.ws13.qse01.gui.SinglePictureFrameController.showTags(SinglePictureFrameController.java:243) 
at at.ac.tuwien.sepm.ws13.qse01.gui.SinglePictureFrameController.setPicture(SinglePictureFrameController.java:196) 
at at.ac.tuwien.sepm.ws13.qse01.gui.MainFrameController.viewSinglePicture(MainFrameController.java:382) 
at at.ac.tuwien.sepm.ws13.qse01.gui.ThumbnailFrameController.openSingleImage(ThumbnailFrameController.java:281) 
at at.ac.tuwien.sepm.ws13.qse01.gui.ThumbnailFrameController.access$600(ThumbnailFrameController.java:37) 
at at.ac.tuwien.sepm.ws13.qse01.gui.ThumbnailFrameController$2.handle(ThumbnailFrameController.java:251) 
at at.ac.tuwien.sepm.ws13.qse01.gui.ThumbnailFrameController$2.handle(ThumbnailFrameController.java:226) 
at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:69) 
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:217) 
at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:170) 
at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:38) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:37) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:35) 
at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:92) 
at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:53) 
at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:33) 
at javafx.event.Event.fireEvent(Event.java:171) 
at javafx.scene.Scene$ClickGenerator.postProcess(Scene.java:3100) 
at javafx.scene.Scene$ClickGenerator.access$8600(Scene.java:3038) 
at javafx.scene.Scene$MouseHandler.process(Scene.java:3320) 
at javafx.scene.Scene$MouseHandler.process(Scene.java:3151) 
at javafx.scene.Scene$MouseHandler.access$1900(Scene.java:3106) 
at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1563) 
at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2248) 
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:250) 
at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:173) 
at java.security.AccessController.doPrivileged(Native Method) 
at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:292) 
at com.sun.glass.ui.View.handleMouseEvent(View.java:530) 
at com.sun.glass.ui.View.notifyMouse(View.java:924) 
at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method) 
at com.sun.glass.ui.gtk.GtkApplication$3$1.run(GtkApplication.java:89) 
at java.lang.Thread.run(Thread.java:744) 

我会非常感谢任何帮助，谢谢！

Answer 1

从你的配置，你可以看到你注入工具箱服务只为TagListFrame类对象：

<bean id="TagListFrame" name="TagListFrame" class="TagListFrame" scope="singleton"> 
    <property name="toolBox" ref="ToolBoxService"/> 
</bean> 

如果要注入相同的服务为其他控制器则必须指定此注射在XML相同您为TagListFrame所做的一切。像这样的

<bean id="MyNewController" name="MyNewController" class="MyNewController" scope="singleton"> 
    <property name="toolBox" ref="ToolBoxService"/> 
</bean> 

P.S. Singleton是默认范围，因此您不需要明确指定它。