当我尝试将https://vaadin.com/directory#addon/vaadin-charts添加到我的Vaadin项目时，我收到以下错误：
显示java.lang.NullPointerException
at org.openide.filesystems.FileUtil.copy(FileUtil.java:559)
at org.vaadin.netbeans.maven.directory.KnownLicense.getText(KnownLicense.java:51)
at org.vaadin.netbeans.maven.directory.AbstractLicenseChooser.acceptLicense(AbstractLicenseChooser.java:75)
at org.vaadin.netbeans.maven.directory.AbstractLicenseChooser.getLicense(AbstractLicenseChooser.java:47)
at org.vaadin.netbeans.maven.project.VaadinAction$AddonHandler.getLicense(VaadinAction.java:503)
at org.vaadin.netbeans.maven.project.VaadinAction$1.actionPerformed(VaadinAction.java:214)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2346)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.AbstractButton.doClick(AbstractButton.java:376)
at javax.swing.plaf.basic.BasicMenuItemUI.doClick(BasicMenuItemUI.java:833)
at javax.swing.plaf.basic.BasicMenuItemUI$Handler.mouseReleased(BasicMenuItemUI.java:877)
at java.awt.Component.processMouseEvent(Component.java:6527)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3321)
at java.awt.Component.processEvent(Component.java:6292)
at java.awt.Container.processEvent(Container.java:2234)
at java.awt.Component.dispatchEventImpl(Component.java:4883)
at java.awt.Container.dispatchEventImpl(Container.java:2292)
at java.awt.Component.dispatchEvent(Component.java:4705)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4898)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4533)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4462)
at java.awt.Container.dispatchEventImpl(Container.java:2278)
at java.awt.Window.dispatchEventImpl(Window.java:2739)
at java.awt.Component.dispatchEvent(Component.java:4705)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:746)
at java.awt.EventQueue.access$400(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:697)
at java.awt.EventQueue$3.run(EventQueue.java:691)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.awt.EventQueue$4.run(EventQueue.java:719)
at java.awt.EventQueue$4.run(EventQueue.java:717)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(ProtectionDomain.java:75)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:716)
at org.netbeans.core.TimableEventQueue.dispatchEvent(TimableEventQueue.java:159)
[catch] at java.awt.EventDispatchThread.pumpOneEventForFilters（EventDispatchThread.java:201） at java.awt.EventDispatchThread.pumpEventsForFilter（EventDispatchThread.java:116） at java.awt.EventDispatchThread.pumpEventsForHierarchy（EventDispatchThread.java:105） at java.awt.EventDispatchThread.pumpEvents（EventDispatchThread.java:101） at java.awt.EventDispatchThread.pumpEvents（EventDispatchThread.java:93） 在java.awt.EventDispatchThread.run（EventDispatchThread.java:82）
我在使用Netbeans 8.这是我第一次使用Vaadin。我按照https://vaadin.com/blog/-/blogs/what-is-so-great-about-vaadin-netbeans-plugin视频中显示的步骤进行操作。没有调整项目依赖性。然而，“感觉”就像一个依赖问题。
TIA。
答案 0 :(得分：1)
根据错误，看起来缺少加载项的许可证。不能从错误堆栈跟踪中确切地说，但看起来像缺少cval-3许可证文本that has been just added。
你可以做的不多，但等待插件更新。或者尝试使用另一个具有不同许可证的附加组件。
答案 1 :(得分：0)
Vaadin NetBeans插件的1.1.3版今天发布并修复了这个问题。你应该更新。