Gradle Build fails with Javadoc NullPointerException

Question

I've just updated one of my projects to Android L with the new build-tools 21.0.2 and the new gradle 2.1.

Now as soon as i build the project on my system i get the following exception:

import com.tundem.aboutlibraries.R;
                                ^
  symbol:   class R
  location: package com.tundem.aboutlibraries
java.lang.NullPointerException
    at com.sun.tools.javadoc.TypeMaker.getType(TypeMaker.java:83)
    at com.sun.tools.javadoc.TypeMaker.getType(TypeMaker.java:44)
    at com.sun.tools.javadoc.ClassDocImpl.superclassType(ClassDocImpl.java:496)
    at com.sun.tools.doclets.internal.toolkit.util.Util.getAllInterfaces(Util.java:459)

4 warnings
    at com.sun.tools.doclets.internal.toolkit.util.Util.getAllInterfaces(Util.java:497)
    at com.sun.tools.doclets.internal.toolkit.util.ClassTree.processType(ClassTree.java:194)
    at com.sun.tools.doclets.internal.toolkit.util.ClassTree.buildTree(ClassTree.java:146)
    at com.sun.tools.doclets.internal.toolkit.util.ClassTree.<init>(ClassTree.java:91)
    at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.startGeneration(AbstractDoclet.java:123)
    at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.start(AbstractDoclet.java:83)
    at com.sun.tools.doclets.formats.html.HtmlDoclet.start(HtmlDoclet.java:63)
    at com.sun.tools.doclets.standard.Standard.start(Standard.java:39)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:606)
    at com.sun.tools.javadoc.DocletInvoker.invoke(DocletInvoker.java:280)
    at com.sun.tools.javadoc.DocletInvoker.start(DocletInvoker.java:160)
    at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:397)
    at com.sun.tools.javadoc.Start.begin(Start.java:167)
    at com.sun.tools.javadoc.Main.execute(Main.java:59)
    at com.sun.tools.javadoc.Main.main(Main.java:49)
:sample:lintVitalRelease FAILED

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':library:generateDebugJavadoc'.
> Javadoc generation failed. Generated Javadoc options file (useful for troubleshooting): '/home/gitlab_ci_runner/gitlab-ci-runner/tmp/builds/project-9/library/build/tmp/generateDebugJavadoc/javadoc.options'

If i build the same project in Android Studio there are no issues. Just on my build-server (with ubuntu)

Is there a way how i can disable the Javadoc generation, or how i can fix this issue.

The only info i found was that this happens if there's a unicode character in the project, but i haven't added one.

I've also added the appcompat and support library.

Thanks.

Answer 1

The solution to fix this issue was to remove all html formatted tags within my method documentations.

In some of the comments i had self closing html elements which caused some issues.

But I still haven't found out why they've changed this with the newest version.