2016-05-29 26 views
1

我有這種方法應該返回一個OberservableList,用於JavaFX ListView,其中包含currentUserPath(默認初始化爲System.getProperty("user.home"))文件的名稱。java - 閱讀用戶文件系統返回AccessDeniedException

public ObservableList<String> getUserItems(){ 
     ObservableList<String> fileList = FXCollections.observableArrayList(); 
     try { 
      Files.walk(Paths.get(currentUserPath)).forEach(filePath -> { 
        if (Files.isRegularFile(filePath)) { 
         fileList.add(filePath.getFileName().toString()); 
        } 
       }); 
     } catch (IOException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } 
     return fileList; 

    } 

不幸的是,我在調用此方法時得到AccessDeniedException。這裏的堆棧跟蹤:

Exception in thread "JavaFX Application Thread" java.lang.RuntimeException: java.lang.reflect.InvocationTargetException 
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1774) 
    at javafx.fxml.FXMLLoader$ControllerMethodEventHandler.handle(FXMLLoader.java:1657) 
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:86) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) 
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74) 
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:49) 
    at javafx.event.Event.fireEvent(Event.java:198) 
    at javafx.scene.Node.fireEvent(Node.java:8411) 
    at javafx.scene.control.Button.fire(Button.java:185) 
    at com.sun.javafx.scene.control.behavior.ButtonBehavior.mouseReleased(ButtonBehavior.java:182) 
    at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:96) 
    at com.sun.javafx.scene.control.skin.BehaviorSkinBase$1.handle(BehaviorSkinBase.java:89) 
    at com.sun.javafx.event.CompositeEventHandler$NormalEventHandlerRecord.handleBubblingEvent(CompositeEventHandler.java:218) 
    at com.sun.javafx.event.CompositeEventHandler.dispatchBubblingEvent(CompositeEventHandler.java:80) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:238) 
    at com.sun.javafx.event.EventHandlerManager.dispatchBubblingEvent(EventHandlerManager.java:191) 
    at com.sun.javafx.event.CompositeEventDispatcher.dispatchBubblingEvent(CompositeEventDispatcher.java:59) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:58) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.BasicEventDispatcher.dispatchEvent(BasicEventDispatcher.java:56) 
    at com.sun.javafx.event.EventDispatchChainImpl.dispatchEvent(EventDispatchChainImpl.java:114) 
    at com.sun.javafx.event.EventUtil.fireEventImpl(EventUtil.java:74) 
    at com.sun.javafx.event.EventUtil.fireEvent(EventUtil.java:54) 
    at javafx.event.Event.fireEvent(Event.java:198) 
    at javafx.scene.Scene$MouseHandler.process(Scene.java:3757) 
    at javafx.scene.Scene$MouseHandler.access$1500(Scene.java:3485) 
    at javafx.scene.Scene.impl_processMouseEvent(Scene.java:1762) 
    at javafx.scene.Scene$ScenePeerListener.mouseEvent(Scene.java:2494) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:380) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler$MouseEventNotification.run(GlassViewEventHandler.java:294) 
    at java.security.AccessController.doPrivileged(Native Method) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.lambda$handleMouseEvent$354(GlassViewEventHandler.java:416) 
    at com.sun.javafx.tk.quantum.QuantumToolkit.runWithoutRenderLock(QuantumToolkit.java:389) 
    at com.sun.javafx.tk.quantum.GlassViewEventHandler.handleMouseEvent(GlassViewEventHandler.java:415) 
    at com.sun.glass.ui.View.handleMouseEvent(View.java:555) 
    at com.sun.glass.ui.View.notifyMouse(View.java:937) 
    at com.sun.glass.ui.gtk.GtkApplication._runLoop(Native Method) 
    at com.sun.glass.ui.gtk.GtkApplication.lambda$null$49(GtkApplication.java:139) 
    at java.lang.Thread.run(Thread.java:745) 
Caused by: java.lang.reflect.InvocationTargetException 
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) 
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:498) 
    at sun.reflect.misc.Trampoline.invoke(MethodUtil.java:71) 
    at sun.reflect.GeneratedMethodAccessor1.invoke(Unknown Source) 
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) 
    at java.lang.reflect.Method.invoke(Method.java:498) 
    at sun.reflect.misc.MethodUtil.invoke(MethodUtil.java:275) 
    at javafx.fxml.FXMLLoader$MethodHandler.invoke(FXMLLoader.java:1769) 
    ... 48 more 
Caused by: java.io.UncheckedIOException: java.nio.file.AccessDeniedException: /home/adam/.gconf/apps/gedit-2 
    at java.nio.file.FileTreeIterator.fetchNextIfNeeded(FileTreeIterator.java:88) 
    at java.nio.file.FileTreeIterator.hasNext(FileTreeIterator.java:104) 
    at java.util.Iterator.forEachRemaining(Iterator.java:115) 
    at java.util.Spliterators$IteratorSpliterator.forEachRemaining(Spliterators.java:1801) 
    at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481) 
    at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471) 
    at java.util.stream.ForEachOps$ForEachOp.evaluateSequential(ForEachOps.java:151) 
    at java.util.stream.ForEachOps$ForEachOp$OfRef.evaluateSequential(ForEachOps.java:174) 
    at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234) 
    at java.util.stream.ReferencePipeline.forEach(ReferencePipeline.java:418) 
    at application.FTPDownload.getUserItems(FTPDownload.java:147) 
    at application.FTPController.handleConnectButtonAction(FTPController.java:23) 
    ... 58 more 
Caused by: java.nio.file.AccessDeniedException: /home/adam/.gconf/apps/gedit-2 
    at sun.nio.fs.UnixException.translateToIOException(UnixException.java:84) 
    at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:102) 
    at sun.nio.fs.UnixException.rethrowAsIOException(UnixException.java:107) 
    at sun.nio.fs.UnixFileSystemProvider.newDirectoryStream(UnixFileSystemProvider.java:427) 
    at java.nio.file.Files.newDirectoryStream(Files.java:457) 
    at java.nio.file.FileTreeWalker.visit(FileTreeWalker.java:300) 
    at java.nio.file.FileTreeWalker.next(FileTreeWalker.java:372) 
    at java.nio.file.FileTreeIterator.fetchNextIfNeeded(FileTreeIterator.java:84) 
    ... 69 more 

任何人都可以告訴我爲什麼我可能會得到這個異常?任何幫助將非常感激。

+0

你能告訴我們什麼'System.getProperty(「user.home」)'返回?在你的堆棧跟蹤中,顯然應用程序無法讀取路徑爲「/ home/adam/.gconf/apps/gedit-2」的目錄。 –

回答

1

該異常的Javadoc說:

「[這是] checked異常[是]時,拋出該文件系統操作被拒絕,通常是由於文件權限或其他訪問檢查。」

所以最可能的解釋是應用程序運行的帳戶沒有權限讀取「/home/adam/.gconf/apps/gedit-2」目錄。

+0

你是對的。該目錄沒有讀取權限。 我該如何去檢查這在Java中?我試過'if(Files.isReadable(filePath))'但我仍然得到相同的錯誤。 –

0

這是因爲正在運行的程序無法訪問指定的文件。 從堆棧跟蹤:

Caused by: java.io.UncheckedIOException: java.nio.file.AccessDeniedException: /home/adam/.gconf/apps/gedit-2 
Caused by: java.nio.file.AccessDeniedException: /home/adam/.gconf/apps/gedit-2 

/home目錄和/home/adam/.gconf/apps/gedit-2文件的權限,無論是通過運行程序的用戶訪問。

其他的可能性是沒有這樣的文件/目錄。