4.x Assigning Tracer.global(tracer) with the OpenTelemetry provider throws a spurious exception

[tjquinno]

Environment Details

• Helidon Version: 4.x
• Helidon SE or Helidon MP SE
• JDK version:
• OS:
• Docker version (if applicable):

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Problem Description

The Helidon tracing API allows developer code to set the global tracer by invoking Tracer.global(tracer).

Doing so when using the OpenTelemetry tracing provider causes an incorrect exception to be thrown:

Exception in thread "main" java.lang.IllegalArgumentException: Tracer must be an instance of Helidon OpenTelemetry tracer. Please use HelidonOpenTelemetry to create such instance
        at io.helidon.tracing.providers.opentelemetry.OpenTelemetryTracerProvider.global(OpenTelemetryTracerProvider.java:133)
        at io.helidon.tracing.TracerProviderHelper.global(TracerProviderHelper.java:80)
        at io.helidon.tracing.Tracer.global(Tracer.java:50)

This happens even if the provided tracer is indeed a HelidonOpenTelemetry object.

Steps to reproduce

With a dependency on helidon-tracing-providers-opentelemetry and helidon-tracing-api add code something like this:

        io.opentelemetry.api.trace.Tracer otelTracer = openTelemetry.getTracer(serviceName);
        Tracer helidonTracer = HelidonOpenTelemetry.create(openTelemetry, otelTracer, Map.of());
        Tracer.global(helidonTracer);

The last line triggers the exception even though the provided tracer is of the correct type.