May I get source code or only modified class?

[irbistwo]

May I get source code on classwriter?
For example of HttpRequestParser(Undertow) ..its generated to HttpRequestParser$$generated.class(using org.jboss.classfilewriter)
I was researching how Undertow working /Get dependences/Up on IDE(JDeveloper) ,
wanted trace (debug )way request /response, but discovered what way go out in HttpRequestParser$$generayed.class.
This one is a generated tricky, complicate process, of «parser-generator»(io.undertow.annotationprocessor use
org.jboss.classfilewriter
https://github.com/undertow-io/undertow/tree/master/parser-generator/src/main/java/io/undertow/annotationprocessor
)
and I did not found
HttpRequestParser$$generayed.java in annotation-source target.
I was writed
com.sun.tools.javac.Main.main (new String[] {"-proc:only", "-processor", "io.undertow.annotationprocessor.HttpParserAnnotationProcessor", "HttpRequestParser.java"});

Append code to HttpParserAnnotationProcessor(process)
JavaFileObject jfo = filer.createSourceFile(classElement.getQualifiedName() + "Info");

But I get only class file and empty source file;
How I can get source code for annotation? May I modyfy code to get source?(or jboss-classfilefriter working only class files?)

(On undertow within portal does not exist issue
Writed on https://issues.redhat.com/projects/UNDERTOW
No answer.
)