RFR: JDK-8250766: javadoc adds redundant spaces when @see program element is wrapped [v3]

[Hannes Wallnöfer]

On Wed, 5 May 2021 10:27:57 GMT, Pavel Rappo <prappo at openjdk.org> wrote:

> 
> > Yes, it can. This is covered by test/langtools/jdk/javadoc/doclet/testTagMisuse/TestTagMisuse.java
> 
> I think it's an empty string that ReferenceTree.getSignature can return, not null. To check that, I modified DCReference as follows and ran the tests (including TestTagMisuse), which all passed:
> 
> ```
>          DCReference(String signature, JCTree.JCExpression moduleName, JCTree qualExpr, Name member, List<JCTree> paramTypes) {
> -            this.signature = signature;
> +            this.signature = Objects.requireNonNull(signature);
> ```

You are right, it is it is not `DCReference` that returns `null` but `CommentHelper#getReferencedSignature`, which returns null as default value if there is no reference object to get the signature from. Among the uses of this method there is one that doesn't do a null check, but there's also one that handles `null` differently than `""`. I don't think the issue is serious enough to warrant a separate bug, so I'll just add the missing null check in my final commit.

-------------

PR: https://git.openjdk.java.net/jdk/pull/3754