[JAVA] Errore javadoc

[kadorit]

Mi sapreste dire che significa questo errore?

java.lang.NullPointerException
at com.sun.tools.doclets.formats.html.PackageUseWriter.generatePackageUse(PackageUseWriter.java:180)
at com.sun.tools.doclets.formats.html.PackageUseWriter.generatePackageList(PackageUseWriter.java:124)
at com.sun.tools.doclets.formats.html.PackageUseWriter.generatePackageUse(PackageUseWriter.java:110)
at com.sun.tools.doclets.formats.html.PackageUseWriter.generatePackageUseFile(PackageUseWriter.java:99)
at com.sun.tools.doclets.formats.html.PackageUseWriter.generate(PackageUseWriter.java:78)
at com.sun.tools.doclets.formats.html.ClassUseWriter.generate(ClassUseWriter.java:116)Generating C:\Documents and Settings\kabul\Desktop\ContoBancoPosta\BancoPosta\doc\package-use.html...

at com.sun.tools.doclets.formats.html.HtmlDoclet.generateOtherFiles(HtmlDoclet.java:92)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.startGeneration(AbstractDoclet.java:122)
at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.start(AbstractDoclet.java:64)
at com.sun.tools.doclets.formats.html.HtmlDoclet.start(HtmlDoclet.java:42)
at com.sun.tools.doclets.standard.Standard.start(Standard.java:23)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
at java.lang.reflect.Method.invoke(Method.java:585)
at com.sun.tools.javadoc.DocletInvoker.invoke(DocletInvoker.java:269)
at com.sun.tools.javadoc.DocletInvoker.start(DocletInvoker.java:143)
at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:340)
at com.sun.tools.javadoc.Start.begin(Start.java:128)
at com.sun.tools.javadoc.Main.execute(Main.java:41)
at com.sun.tools.javadoc.Main.main(Main.java:31)

[kadorit]

Ho notato che questo errore lo ho solo quando seleziono anche il package di default. Che faccio??