Updates documentation on gh-pages website (WIP)

[manoelcampos]

Hello, I'm re-reading Byte Buddy's documentation and found some issues I can fix.
This PR is WIP and I let you know when I'm done.
I'm sending it in advance in order to discuss some issues I've found.
You can check the live changes at https://manoelcampos.github.io/byte-buddy/

Some issues to discuss

JDK version on GitHub Workflow

If you take a look at https://manoelcampos.github.io/byte-buddy/#/develop, it currently states that:

The GitHub Action is configured to compile and test the project for the Open JDK versions 6 and 7 and the Oracle JDK versions 7 and 8.

This information is not accurate, since there are tests for the Oracle JDK 8, 11, 17, 21 (hotspot-supported version).
But there are tests for JDK 6 and 7 (hotspot-legacy). In fact, this workflow provides lots of tests for different JDK distributions and versions. Maybe, the documentation would just state that:

The GitHub Action is configured to compile and test the project for different versions of Open JDK and the Oracle JDK.

• The sentence was changed to: "The GitHub Action is configured to compile and test the project for different versions of OpenJDK, Oracle JDK and other distributions, starting from JDK 6 up to the latest release (despite deprecated JDK releases are not supported anymore)."

Minimum JDK version required

The welcome page at https://manoelcampos.github.io/byte-buddy/ says that:

Byte Buddy is written in Java 5

Contradictorily, https://manoelcampos.github.io/byte-buddy/#/develop, states:

All this implies that you need to write Java code that is compatible to a Java 6 compiler.

• Indicates that Byte Buddy is a Java 6 library, since the minimum JDK version on the workflow is JDK 6.

Develop page

• I'm not sure what you meant here: "All code is to be documented what makes this property easier to validate by automatic checks"

• Is the following sentence still true?

Java 9 support is currently still experimental."

The CI workflow shows that Java 9 is unsupported. But I'm not sure if that is because this JDK version is deprecated or if the support was not complete.

• Is the following sentence still true?

As of Java 8, Byte Buddy not currently support the following functionality.

Tutorial page

The link about inflation mechanism used for reflection is broken.
The only reference I could find was this one.

However, this inflation mechanism seems to be dropped in JDK 18, being replaced by method handles (I'm not sure about that). This way, I think the sentence below needs to be rewritten:

However, modern JVMs know a concept called inflation where the JNI-based method invocation is replaced by generated byte code that is injected into a dynamically created class.

• I updated the entire paragraph including information about JDK releases before and after 18.

• It's not clear what you mean by "Benchmark (2a)" and other references. There are no such references on the table.

• The sentence "Also, if example.Bar extended example.Foo, any overridden package-private methods would become inoperative but would delegate to the original implementations." is confusing.

• Is the following sentence still true? "Furthermore, Byte Buddy currently only takes loaded classes as its argument, this will change in future versions where the existing API can be used to equally work with unloaded classes."

• At "From the above example, it is obvious that the super method is called by injecting some instance of a Callable into the LoggerInterceptor which invokes the original, non-overridden implementation of MemoryDatabase#load(String) from its call method. This helper class is called an AuxiliaryType within Byte Buddy's terminology", it's not clear which AuxiliaryType is that. Is it a class that ByteBuddy creates that implements Callable?

[raphw]

That is right, the reflection implementation was dropped when it was retrofitted to use method handles. This also to avoid JNI and its limitations to virtual threads.

[raphw]

This is a great effort if you want to update the documentation. I did not find time to work on it in a long time, and it is rather outdated. It would really need some attention.

[manoelcampos]

Hey @raphw
I'm updating the tutorial page (the last one), but it will take some time. I hope I finish this week.
I updated the comments above and added some checkboxes to track the progress.
I'd need your help on those unchecked ones.