Javaagent doesn't work with java.net.spi.InetAddressResolverProvider

[hermannpencole]

I use opentelemetry-javaagent - version: 1.19.2 :
INFO io.opentelemetry.javaagent.tooling.VersionLogger - opentelemetry-javaagent - version: 1.19.2

I work with java 18 because i need InetAddressResolverProvider : https://docs.oracle.com/en/java/javase/18/docs/api/java.base/java/net/spi/InetAddressResolverProvider.html.
When I launch my app without opentelemetry-javaagent the InetAddressResolverProvider works.
When I launch my app with opentelemetry-javaagent the InetAddressResolverProvider doesn't works.

[mateuszrzeszutek]

The agent probably loads the resolver first, using the agent classloader (not the system CL, as the Javadoc suggests): https://github.com/openjdk/jdk/blob/f2acdfdcbd2a49c1167656e73b67b38b545f9472/src/java.base/share/classes/java/net/InetAddress.java#L477-L482
We might need to fix the CL before OpenTelemetry is initialized (it most likely resolves the exporter endpoint address)

[hermannpencole]

Tks for your help mateuszrzeszutek : with your comment i found a workaround.
I extract code from my InetAddressResolverProvider into a new jar. And I declare this jar in launch option -Xbootclasspath/a

[serkan-ozal]

This issue is similar to #10921

I have propose the following solution: #10921 (comment)

What do you think about it @mateuszrzeszutek @laurit

[laurit]

@serkan-ozal you are welcome to create a PR. If I were to attempt solving this I'd probably attempt transforming the InetAddress class so that instead of if (VM.isBooted()) it would have something like if (VM.isBooted() && AgentBooted.initialized) the AgentBooted.initialized flag could be set after agent initialization has completed. The transformation would need to be set up before we initialize opentelemetry sdk. Could do something similar to LaunchHelperClassFileTransformer.

[serkan-ozal]

Hmm, thanks for pointing out. Will check LaunchHelperClassFileTransformer

[serkan-ozal]

@laurit Here it is: #11987