[YETUS-627] Doclet does not work with Gradle Javadoc generation

• Type: Bug
• Status: Open
• Priority: Major
• Resolution: Unresolved
• Component/s: Audience Annotations
• Environment: Gradle 4.6, Java 1.8.0_121
• Assignee: Unassigned
• Reporter: Grant Henke
• Created: 13/Apr/18 14:16
• Updated: 13/Apr/18 14:16

Description

The IncludePublicAnnotationsStandardDoclet does not work with Gradle Javadoc generation, though it does for Maven in the same project. It appears Maven passes slightly different arguments to the Javadoc tool. 

In Gradle I configured the Javadoc task to use the Doclet via:

configurations {
   doclet
}

dependencies {
   doclet "org.apache.yetus:audience-annotations:0.7.0"
}

javadoc {
   options.docletpath = configurations.doclet.files.asType(List)
   options.doclet = 'org.apache.yetus.audience.tools.IncludePublicAnnotationsStandardDoclet'
}

Running gradle javadoc results in: 

 

IncludePublicAnnotationsStandardDoclet java.lang.ArrayStoreException: com.sun.proxy.$Proxy2 at java.util.AbstractCollection.toArray(AbstractCollection.java:196) at com.sun.tools.doclets.internal.toolkit.util.IndexBuilder.buildIndexMap(IndexBuilder.java:160) at com.sun.tools.doclets.internal.toolkit.util.IndexBuilder.<init>(IndexBuilder.java:124) at com.sun.tools.doclets.internal.toolkit.util.IndexBuilder.<init>(IndexBuilder.java:103) at com.sun.tools.doclets.formats.html.HtmlDoclet.generateOtherFiles(HtmlDoclet.java:122) at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.startGeneration(AbstractDoclet.java:146) at com.sun.tools.doclets.internal.toolkit.AbstractDoclet.start(AbstractDoclet.java:82) at com.sun.tools.doclets.formats.html.HtmlDoclet.start(HtmlDoclet.java:80) at com.sun.tools.doclets.standard.Standard.start(Standard.java:39) at org.apache.yetus.audience.tools.IncludePublicAnnotationsStandardDoclet.start(IncludePublicAnnotationsStandardDoclet.java:51) 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 com.sun.tools.javadoc.DocletInvoker.invoke(DocletInvoker.java:310) at com.sun.tools.javadoc.DocletInvoker.start(DocletInvoker.java:189) at com.sun.tools.javadoc.Start.parseAndExecute(Start.java:366) at com.sun.tools.javadoc.Start.begin(Start.java:219) at com.sun.tools.javadoc.Start.begin(Start.java:205) at com.sun.tools.javadoc.Main.execute(Main.java:64) at com.sun.tools.javadoc.Main.main(Main.java:54)

 

Digging into the stack trace a bit it appears that the issue comes from building an index of packages, however Gradle passes the class files to Javadoc and does not pass packages. This is a valid way to generate Javadoc as documented here: https://docs.oracle.com/javase/7/docs/technotes/tools/solaris/javadoc.html#documentingclasses

The Javadoc options Gradle generates are (with path substitutions): 

 

-classpath '/some/classpath/paths/...'
-d '/some/destination/directory'
-doclet 'org.apache.yetus.audience.tools.IncludePublicAnnotationsStandardDoclet'
-docletpath '/path/to/audience-annotations-0.7.0.jar'
-doctitle 'some API'
-quiet 
-windowtitle 'some API'
'/path/to/some/Class.java'
'/path/to/some/Class2.java'
'/path/to/some/Class3.java'
...

There is no great way to add packages to the Javadoc options output in Gradle, but one hacky solution does allow it to successfully generate Javadocs. Forcing a valid package name into the options by passing it with an option that takes no arguments will allow the task to succeed. 

In Gradle I added:

 

javadoc {
   ...
   // A Javadoc option that takes no parameter, 
   // and a valid package as the parameter.
   options.addStringOption("notimestamp", "some.valid.package")
}

This results in the the following javadoc options:

 

 

-classpath '/some/classpath/paths/...'
-d '/some/destination/directory'
-doclet 'org.apache.yetus.audience.tools.IncludePublicAnnotationsStandardDoclet'
-docletpath '/path/to/audience-annotations-0.7.0.jar'
-doctitle 'some API'
-notimestamp 'some.valid.package'
-quiet 
-windowtitle 'some API'
'/path/to/some/Class.java'
'/path/to/some/Class2.java'
'/path/to/some/Class3.java'
...

Note: The packages would generally come just before the list of classes per the documentation, but this seams to work for some reason. (https://docs.oracle.com/javase/7/docs/technotes/tools/solaris/javadoc.html#documentingboth)

 

When running gradle javadoc there may be a warning like below when using this hacky workaround:

javadoc: warning - No source files for package some.valid.package