IO-845 PathUtils.copyDirectory copies or follows symbolic links

[peterdemaeyer]

Defined the behavior of PathUtils.copyDirectory for symbolic links. It depends on the option LinkOption.NOFOLLOW_LINKS. Non-symbolic (hard) links are out of scope, given that the copy behavior for them was already well-defined: they're treated as regular files.
For the sake of conciseness, the following paragraphs use the term "link" for "symbolic link".

Without NOFOLLOW_LINKS option:

• Links are followed, so that there are no links in the target directory.
• Cyclic links result in FileSystemLoopException.
• Broken links are ignored, they are not copied at all.

With NOFOLLOW_LINKS option:

• Links are copied as links, so that there are links in the target directory for every link in the source directory.
• Links that link to a file or directory inside the source directory are copied to relative links inside the target directory, linking to the copied file or directory.
• Links that link to a file or directory outside the source directory are copied to links inside the target directory, linking to the same file or directory as the link in the source directory.
• Cyclic links are preserved, mirrored to cyclic links in the target directory.
• Broken links are ignored, they are not copied at all.

All of this is also explained in the updated JavaDoc.

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[garydgregory]

Hello @peterdemaeyer !
I have a comment in the copy visitor, and a small implementation issue about comparing enums.

[garydgregory]

Hello @peterdemaeyer

Thank you for your update. You'll want to run mvn by itself before you push to run all build checks; this runs the default Maven goal as defined in the POM.

[garydgregory]

Hi @peterdemaeyer

Trying to use headers like <h4> in Javadoc is an exercise in frustration. Different versions seems to have different rules. We do use <h2> without errors, for example in org.apache.commons.lang3.function.MethodInvokers's class Javadoc. I don't think you can use an HTML header in a way that'll work across all the versions we support, all LTS versions. I would keep it simple and use <strong> or <em>.

[peterdemaeyer]

Hi, beware that I’m on vacation this week, only phone access ans no GitHub access. Don’t expect an update before Sunday. The reason I used <h4> is because it’s an official/default JavaDoc guideline. I don’t have the reference here, I’ll reply more in detail when I’m back from vacation. Anyway, I have no problem changing it, I just wanted to point out that I didn’t invent it out of thin air. Op vr 13 feb 2026 om 22:21 schreef Gary Gregory ***@***.***>

…

*garydgregory* left a comment (apache/commons-io#827) <#827 (comment)> Hi @peterdemaeyer <https://github.com/peterdemaeyer> Trying to use headers like <h4> in Javadoc is an exercise in frustration. Different versions seems to have different rules. We do use <h2> without errors, for example in org.apache.commons.lang3.function.MethodInvokers's class Javadoc. — Reply to this email directly, view it on GitHub <#827 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAK7WUUYP5XKNBPJZQODPT34LY55ZAVCNFSM6AAAAACUEP6SS6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTQOJZGU2DQMZYHA> . You are receiving this because you were mentioned.Message ID: ***@***.***>

[garydgregory]

Enjoy your vacation! Gary

…

On Sat, Feb 14, 2026, 16:27 Peter De Maeyer ***@***.***> wrote: *peterdemaeyer* left a comment (apache/commons-io#827) <#827 (comment)> Hi, beware that I’m on vacation this week, only phone access ans no GitHub access. Don’t expect an update before Sunday. The reason I used <h4> is because it’s an official/default JavaDoc guideline. I don’t have the reference here, I’ll reply more in detail when I’m back from vacation. Anyway, I have no problem changing it, I just wanted to point out that I didn’t invent it out of thin air. Op vr 13 feb 2026 om 22:21 schreef Gary Gregory ***@***.***> > *garydgregory* left a comment (apache/commons-io#827) > <#827 (comment)> > > Hi @peterdemaeyer <https://github.com/peterdemaeyer> > > Trying to use headers like <h4> in Javadoc is an exercise in frustration. > Different versions seems to have different rules. We do use <h2> without > errors, for example in org.apache.commons.lang3.function.MethodInvokers's > class Javadoc. > > — > Reply to this email directly, view it on GitHub > <#827 (comment)>, > or unsubscribe > < https://github.com/notifications/unsubscribe-auth/AAK7WUUYP5XKNBPJZQODPT34LY55ZAVCNFSM6AAAAACUEP6SS6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTQOJZGU2DQMZYHA> > . > You are receiving this because you were mentioned.Message ID: > ***@***.***> > — Reply to this email directly, view it on GitHub <#827 (comment)>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/AAJB6N3YZVP6RCZAKEMJKAD4L6HM7AVCNFSM6AAAAACUEP6SS6VHI2DSMVQWIX3LMV43OSLTON2WKQ3PNVWWK3TUHMZTSMBSGU2TEMJTGY> . You are receiving this because you commented.Message ID: ***@***.***>

[peterdemaeyer]

Hi @peterdemaeyer

Trying to use headers like <h4> in Javadoc is an exercise in frustration. Different versions seems to have different rules. We do use <h2> without errors, for example in org.apache.commons.lang3.function.MethodInvokers's class Javadoc. I don't think you can use an HTML header in a way that'll work across all the versions we support, all LTS versions. I would keep it simple and use \<strong\> or \<em\>.

Okay, I'll change it, but beware that I didn't randomly pick <h4>, I was following this specification that says: "headings in the documentation comments for constructors, methods, fields and other members should start at heading level 4."

Your own example of <h2> for class JavaDoc is also in line with that same specification by the way: "comments for module, package, and type declarations (including nested types) should start at heading level 2".

[peterdemaeyer]

Enjoy your vacation! Gary

Thanks! I noticed you addressed your comment while I was on vacation. Perfect.