8348282: Add option for syntax highlighting in javadoc snippets

[hns]

Please review a change to add a javadoc option to enable syntax highlighting for code fragments in snippets and <pre><code> tags. The new --syntax-highlight option uses the [highlight.js] JavaScript library and supports Java, Properties, XML, HTML and JSON. The option is enabled in the JDK API docs target, generated output is available here.

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Progress

• Change requires CSR request JDK-8352691 to be approved
• Change must not contain extraneous whitespace
• Commit message must refer to an issue
• Change must be properly reviewed (2 reviews required, with at least 2 Reviewers)

Issues

• JDK-8348282: Add option for syntax highlighting in javadoc snippets (Enhancement - P3)
• JDK-8352691: Add option for syntax highlighting in javadoc snippets (CSR)

Reviewers

• Erik Joelsson (@erikj79 - Reviewer) 🔄 Re-review required (review applies to dd766914)

Reviewing

Using git

Checkout this PR locally:
$ git fetch https://git.openjdk.org/jdk.git pull/24417/head:pull/24417
$ git checkout pull/24417

Update a local copy of the PR:
$ git checkout pull/24417
$ git pull https://git.openjdk.org/jdk.git pull/24417/head

Using Skara CLI tools

Checkout this PR locally:
$ git pr checkout 24417

View PR using the GUI difftool:
$ git pr show -t 24417

Using diff file

Download this PR as a diff file:
https://git.openjdk.org/jdk/pull/24417.diff

Using Webrev

Link to Webrev Comment

[bridgekeeper]

👋 Welcome back hannesw! A progress list of the required criteria for merging this PR into master will be added to the body of your pull request. There are additional pull request commands available for use with this pull request.

[openjdk]

❗ This change is not yet ready to be integrated.
See the Progress checklist in the description for automated requirements.

[openjdk]

@hns The following labels will be automatically applied to this pull request:

• build
• javadoc

When this pull request is ready to be reviewed, an "RFR" email will be sent to the corresponding mailing lists. If you would like to change these labels, use the /label pull request command.

[mlbridge]

Webrevs

• 03: Full - Incremental (05fc1a4a)
• 02: Full - Incremental (af50d173)
• 01: Full - Incremental (2700131d)
• 00: Full (dd766914)

[erikj79]

Build change looks trivially good.

/reviewers 2 reviewer

[openjdk]

@erikj79
The total number of required reviews for this PR (including the jcheck configuration and the last /reviewers command) is now set to 2 (with at least 2 Reviewers).

[hns]

Here's a selection of code fragments from the sample docs using syntax highlighting:

• Thread example
• Doclet example
• PropertyResourceBundle
• ListResourceBundle
• ClassFile example
• MethodHandles example