运行时保留Javadoc元数据？

Question

Is there any way to access Javadoc information via reflection, the way annotations can be retained at runtime?

If not, how does Eclipse access the javadoc for .jar files?

Answer 1

JavaDoc is not available via reflection. Eclipse and other IDE's access jar files with JavaDoc for libraries where this is available. Ie if you use maven, jar files with JavaDoc is usually distributed along with jar files with the byte code.

Answer 2

Comments used for Javadoc are never retained in compiled classes (see http://java.sun.com/docs/books/jvms/second_edition/ClassFileFormat-Java5.pdf for instance). Eclipse is able to associate Javadoc to the referenced jar files either by extracting it from the jar (if present), by direct association with the jar file (set by yourself or a plugin like m2eclipse), or by finding it inside the JRE javadoc (set directly in "Installed JREs").

Answer 3

You may use this tool to access Javadoc at runtime via annotations. It runs as annotation processor and generates @Description annotations at compile time. https://github.com/Devexperts/dgen

Answer 4

In theory, it would be possible to have a javadoc doclet which is modifying the classes from the javadoc tags, adding some annotations to the documented elements.

But I don't know of any such doclet (which would also have to include some annotation types for runtime use).