java JAXB内容未实例化

Question

好吧，我不知所措。我在这行有一个空指针：

    JAXBContext             context         = JAXBContext.newInstance( X3D.class );

下面是输出错误：

Exception in thread "main" java.lang.NullPointerException
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.checkOverrideProperties(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.SingleElementNodeProperty.<init>(Unknown Source)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.PropertyFactory.create(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.ArrayElementProperty.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.ArrayElementNodeProperty.<init>(Unknown Source)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.PropertyFactory.create(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.SingleElementNodeProperty.<init>(Unknown Source)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
    at sun.reflect.NativeConstructorAccessorImpl.newInstance(Unknown Source)
    at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(Unknown Source)
    at java.lang.reflect.Constructor.newInstance(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.property.PropertyFactory.create(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.ClassBeanInfoImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.getOrCreate(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl.<init>(Unknown Source)
    at com.sun.xml.internal.bind.v2.runtime.JAXBContextImpl$JAXBContextBuilder.build(Unknown Source)
    at com.sun.xml.internal.bind.v2.ContextFactory.createContext(Unknown Source)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
    at java.lang.reflect.Method.invoke(Unknown Source)
    at javax.xml.bind.ContextFinder.newInstance(Unknown Source)
    at javax.xml.bind.ContextFinder.newInstance(Unknown Source)
    at javax.xml.bind.ContextFinder.find(Unknown Source)
    at javax.xml.bind.JAXBContext.newInstance(Unknown Source)
    at javax.xml.bind.JAXBContext.newInstance(Unknown Source)
    at com.prim.esaa.gui.x3d.MyXmlWriter.myWriteFile(MyXmlWriter.java:159)
    at com.prim.esaa.gui.x3d.MyXmlWriter.myWrite(MyXmlWriter.java:199)
    at com.prim.esaa.gui.x3d.Sim3DAnimator.writeXMLoutput(Sim3DAnimator.java:266)
    at com.prim.esaa.gui.x3d.Sim3DAnimator.initModels(Sim3DAnimator.java:212)
    at com.prim.esaa.gui.x3d.Sim3DAnimator.main(Sim3DAnimator.java:141)

我意识到并不是所有的代码都在那里，我可以添加更多，但如果我理解正确，这个命令会设置一些东西，并且完全不依赖于我的任何其他变量。它开始工作，然后就停止了。我不知道为什么

它一遍又一遍地说“未知源”，但我包含了路径和类X3D，所以应该可以

谢谢

Answer 1

试试JAXB的另一个版本，看http://java.net/jira/browse/JAXB-860