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[Bug][java] Missing Log4j dependencies in IDE support

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Assessment

Difficulty
2/5
Estimated time
1-3 hours
Newbie friendliness
72/100
Issue type
Bug
Clarity
Mostly clear
Activity status
Active
Tech stack
java
Domain
build-system, desktop-dev

Research direction

Start with ide-support/pom.xml and inspect how its dependencies relate to the runtime module’s provided Log4j dependencies and the change referenced in issue #954. Reproduce the failure with the described IntelliJ IDEA run configuration for WorkflowSingleAgentExample; done means the local Java example runs without the NoClassDefFoundError and the IDE support dependency is appropriate.

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Description

bug priority/major
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Description

Running the Java example locally fails with:

NoClassDefFoundError: org/apache/logging/log4j/core/Layout

It looks like the Log4j dependencies are missing from the IDE classpath because runtime declares them as provided. This may be related to #954, which removed them from plan.

Adding the following to ide-support/pom.xml resolved the missing-class error in local testing. It also pulls in log4j-api and log4j-core. Would this be an appropriate fix?

<dependency>
    <groupId>org.apache.logging.log4j</groupId>
    <artifactId>log4j-slf4j-impl</artifactId>
    <version>${log4j2.version}</version>
</dependency>
How to reproduce
  1. Import the project into IntelliJ IDEA.
  2. Create a run configuration for org.apache.flink.agents.examples.WorkflowSingleAgentExample, using the examples module classpath.
  3. Enable "Add dependencies with provided scope to classpath" and run it.
Version and environment
  • Flink Agents: 0.4-SNAPSHOT, main (99103da6)
  • Flink: 2.3.0
  • Java: OpenJDK 17.0.15
Are you willing to submit a PR?
  • I'm willing to submit a PR!
Dominant language
Java
Stars
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Forks
171
Avg merge
3d 17h
Merged PRs (30d)
62

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