Invalid "self-closing element not allowed" JavaDoc error

David M. Lloyd david.lloyd at
Thu Jul 25 17:41:55 UTC 2013

On 07/25/2013 12:27 PM, Nick Williams wrote:
> My apologies if this is not the right place to address this. If so, please forgive and direct me to the correct list.
> There are a lot of people/projects complaining about Java 8's new "self-closing element not allowed" error when compiling JavaDoc that has legal <br /> tags in it (just google "self-closing element not allowed" in quotes). Some (including myself) are asking, "Why should we fix this? The problem is not in the JavaDoc, it's in the JavDoc compiler." However, I haven't been able to find anyone who has actually broached the subject on any mailing lists.
> <br /> is completely legal. While it is not strictly required by the HTML standard (unless you're using XHTML), using self-closing tags is /preferred/ because it's more obvious what the intention is. Perhaps most importantly, <br /> is supported on 100% of browsers and is used throughout JavaDoc all over the place. I have a feeling that once more projects start compiling on a released Java 8, this is going to make a fair number of people angry that hey have to "fix" (read: needlessly change) potentially thousands of classes' worth of JavaDoc.
> What was the motivation behind the new "self-closing element not allowed" check and how can we make it go away?

Not really having a stake in this, I just want to observe a couple 
things.  First, from what I can see, the HTML 4.x specifications make no 
reference to self-closing elements or their syntactical realization.  As 
far as I can tell (not being any kind of SGML expert), self-closing 
elements are not valid or meaningful HTML according to its SGML definition.

Finally, even if they were allowed, the BR tag is explicitly defined to 
forbid an end tag; self-closing elements imply an end tag (at least they 
do in XML, which appears to be the next-nearest concrete specification 
that has anything to say on the matter).

See for more info.

So I'm curious when you say "using self-closing tags is /preferred/", do 
you have any sources to cite?

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