apache / apache/logging-log4j2

Log4j pollutes downstream compile classpaths, for example making compilation slower

Open
#4,034 9 comments 0 reactions 1 assignee Claimed by @ppkarwasz View on GitHub
Dominant language
Java
Stars
3.6k
Forks
1.7k
Avg merge
21h 30m
Merged PRs (30d)
27

Description

## Description

Log4j since version 2.25 publishes Gradle Module Metadata.

In the Gradle Module Metadata it declares dependencies on 5 libraries that only contain annotations and that are only used to annotate code, not anywhere in the API.

These dependencies should not be exposed in the `apiElements` variant as that just pollutes the downstream compile classpaths.

Annotations for which no classfile is present are ignored by the JVM.

If someone wants to use those annotations, that someone is responsible to add the annotation to the classpath.

If this was added to work-around the problem that you get a warning (and with `-Werror` an error) from the Java compiler about missing class files for enum constants used in annotations, this is a bug in the Java compiler (https://bugs.openjdk.org/browse/JDK-8305250) and should imho not be worked-around on the library-level.

As you can for example read at https://mail.openjdk.org/pipermail/jdk-dev/2024-October/009459.html and https://bugs.openjdk.org/browse/JDK-6322301, annotations for which no classfile is present should be ignored by the JVM.

This should be fixed by fixing the bug in javac.
As work-around on the client side, one could stop using `-Werror`, disable that specific linting option, or add the dependencies in question to the `compileOnly` configuration.

It is imho not the responsibility of a library to work-around this bug in Javac that is used by downstream projects with special configuration, thereby polluting the compile classpath of all downstream projects even if they don't use that option that makes the warning an error and thus making compilation slower for all downstream projects unless they then manually exclude those dependencies.

## Configuration

**Version:** 2.25+

Contributor guide

No contributing guide indexed for this repository

Assessment

This issue has not been assessed yet.

Get new issues in your inbox

A short digest of beginner-friendly GitHub issues.