invokedynamic instrumentation by default for internal instrumentation

[SylvainJuge]

This is a sub-step of #13031

We have been testing invokedynamic instrumentation in CI for a while, and we need to make progress towards making it the default.

As discussed in 2026-01-22 Java SIG meeting, one of the first steps would be to start with internal instrumentation:

• internal instrumentation have been tested with indy in CI for a while, most of it is already "indy ready" which means it runs inlined by default but can also use indy (opt-in)
• we should not break compatibility with existing extensions and distributions : both can provide their own instrumentation modules.

The goals of this step would be to achieve the following:

• migrate any remaining indy-incompatible internal instrumentation to be indy-compatible.
• make InstrumentationModule.isIndyModule() return true for all internal instrumentation modules and make them use inline = false whenever possible
• remove usages of the isIndyReady method in ExperimentalInstrumentationModule for all internal instrumentation modules.

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Implementation steps

• indy by default for internal instrumentation + muzzle check enable indy by default for internal modules #16753
• ensure that all internal instrumentation modules are "indy-ready"
  • fix internal instrumentation: indy incompatibility with SecurityManager for some internal instrumentation #16821
  • guava-10.0 make guava indy-ready #16989
  • scala-fork-join-2.8
  • hibernate-6.0
  • hibernate-4.0
  • hibernate-3.3
  • hibernate-procedure-call-4.3 make hibernate-procedure-call indy-ready #16984
  • okhttp-2.2 make okttp-2.2 indy ready #16983
  • pekko-actor-1.0 make pekko-actor indy-ready #16982
  • spring-core-2.0 make spring-core indy ready #16981
• maybe wait for a release cycle to wait for feedback from the field (if any)
• isIndyModule() = true + inline = false for internal instrumentation
• remove usages of isIndyReady and deprecate it.
• remove testing in CI by removing -PtestIndy as all internal instrumentation is using indy.

Once this is complete, all internal instrumentation modules are "indy native":

• they should always use indy
• they are no longer influenced by the otel.javaagent.experimental.indy configuration option
• there is no advice transformation applied: it is no longer necessary to modify "indy ready" instrumentation to use inline = false

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Notes

• there are a few internal instrumentations that still require to NOT have inline = false because they are inlined, which means for now inline = false is technically optional but should be used most of the time.
• the otel.javaagent.experimental.indy configuration option would still be useful for testing extensions and distributions compatibility with indy.