Fix(#2769): Modify the annotation processor in 2.x to give a warning if a plugin builder attribute does not have a public setter.

[jaykataria1111]

The following commit modifies the annotation processor in 2.x to shell out a warning if the plugin builder attribute does not have a public setter.

A @SuppressWarnings("log4j.public.setter") attribute can be used to ignore this compilation warning incase it is a known issue.

Checklist

• Base your changes on 2.x branch if you are targeting Log4j 2; use main otherwise
• ./mvnw verify succeeds (if it fails due to code formatting issues reported by Spotless, simply run ./mvnw spotless:apply and retry)
• Non-trivial changes contain an entry file in the src/changelog/.2.x.x directory
• Tests for the changes are provided
• Commits are signed (optional, but highly recommended)

[github-actions]

Job	Requested goals	Build Tool Version	Build Outcome	Build Scan®
build-macos-latest	clean install	3.9.8	❌
build-ubuntu-latest	clean install	3.9.8	❌
build-windows-latest	clean install	3.9.8	❌

Generated by gradle/develocity-actions

[ppkarwasz]

@jaykataria1111,

Thanks for your contribution! I added some minor remarks below.

If you haven't done it already, please sign the ASF ICLA.

[jaykataria1111]

Sounds good @ppkarwasz let me fix and rebase this! 🙂

[ppkarwasz]

LGTM, thanks!

[ppkarwasz]

Suggested change

	private void processBuilderAttributes(final VariableElement element) {
	private void processBuilderAttribute(final VariableElement element) {

Small typo.

[ppkarwasz]

@jaykataria1111,

I sent you an invitation to the Apache Slack to the address you use in your commits.

[jaykataria1111]

Hi @ppkarwasz the build was failing, hence I put the pr in draft 🥲. Thanks for approving it, but I will have to make a revision.

I am not sure I got the slack invitation, was the email [email protected]?

[ppkarwasz]

No, I used the one from you University/Alma Mater that you use for your commits.

[jaykataria1111]

Hi @ppkarwasz i am trying to move away from that email, because I don't have access to that anymore 🥲 will change it in my commits as well! I apologize

[ppkarwasz]

Hi @jaykataria1111,

The OSGi fail is due to an "unauthorized" usage of Commons Lang 3. All optional Maven dependencies, must be explicitly marked as optional in OSGi, if we need them. In this case we don't.

[ppkarwasz]

This is the reason the OSGi builds fail.

We don't have commons-lang3 as direct dependency. It is brought in the project by the optional commons-compress dependency.

BND does not automatically mark optional Maven dependencies as optional OSGi dependencies and for good reasons (see bndtools/bnd#2713 for a discussion), so the OSGi tests detected that the required org.apache.commons.lang3 package is missing. Please don't use Commons Lang 3, we are a bottom-of-the-stack library with no required dependencies.

[ppkarwasz]

Please make this private, we only expose public methods, when we need to.

[ppkarwasz]

Suggested change

	if (StringUtils.isEmpty(fieldName)) return ""; // Return empty string if the field is a blank String.
	return String.format(
	"%s%s",
	fieldName.substring(0, 1).toUpperCase(Locale.ROOT),
	fieldName.substring(1)); // we do not need to Lowercase here examples like field name 'ignoreExceptions'
	return fieldName.isEmpty() ? fieldName : Character.toUpperCase(fieldName.charAt(0)) + fieldName.substring(1);

In this case, we don't need StringUtils.isEmpty(), since the argument is certainly non null. In the cases we need it, we have a copy in o.a.l.l.util.Strings.isEmpty().