apache/beam · error · CannotProvideCoderException

Unable to invoke 'public static CoderProvider getCoderProvid

Error message

Unable to invoke 'public static CoderProvider getCoderProvider()' on %s

What it means

Thrown by DefaultCoder.coderFor when the reflective invocation of getCoderProvider() on the @DefaultCoder-annotated value fails (IllegalAccessException, IllegalArgumentException, InvocationTargetException, NullPointerException, or ExceptionInInitializerError). The method exists but calling it blows up; Beam wraps this in CannotProvideCoderException with the original as the cause.

Source

Thrown at sdks/java/core/src/main/java/org/apache/beam/sdk/coders/DefaultCoder.java:138

        } catch (NoSuchMethodException e) {
          throw new CannotProvideCoderException(
              String.format(
                  "Unable to find 'public static CoderProvider getCoderProvider()' on %s",
                  defaultAnnotationValue),
              e);
        }

        CoderProvider coderProvider;
        try {
          coderProvider =
              Preconditions.checkStateNotNull(
                  (CoderProvider) coderProviderMethod.invoke(clazz /* ignored */));
        } catch (IllegalAccessException
            | IllegalArgumentException
            | InvocationTargetException
            | NullPointerException
            | ExceptionInInitializerError e) {
          throw new CannotProvideCoderException(
              String.format(
                  "Unable to invoke 'public static CoderProvider getCoderProvider()' on %s",
                  defaultAnnotationValue),
              e);
        }
        return coderProvider.coderFor(typeDescriptor, componentCoders);
      }
    }
  }
}

View on GitHub (pinned to 12126d8942)

Solutions

Inspect the cause chain (e.getCause()) to find the real failure inside getCoderProvider() and fix it.
Ensure getCoderProvider() is exactly 'public static CoderProvider getCoderProvider()' on a publicly accessible class.
Remove failing dependencies/static initialization from the coder class; make the provider stateless.
Register the coder programmatically via registerCoderForType to bypass the reflective path entirely.

Example fix

// before
public static CoderProvider getCoderProvider() {
  return new EventCoderProvider(UNINITIALIZED_CONFIG); // NPE
}

// after
public static CoderProvider getCoderProvider() {
  return new EventCoderProvider();
}

Defensive patterns

Strategy: try-catch

Validate before calling

// Fail fast in tests:
Assert.notNull(MyCoder.getCoderProvider(), "getCoderProvider() must return a provider");

Try / catch

try {
  coder = coderRegistry.getCoder(TypeDescriptor.of(MyType.class));
} catch (CannotProvideCoderException e) {
  LOG.error("getCoderProvider() failed; cause:", e.getCause());
  throw e;
}

Prevention

Inspect getCause() — the reflective failure always carries the real root cause.
Keep CoderProvider factories stateless and free of static-initializer dependencies.
Unit-test coder resolution for every custom annotated type.

When it happens

Trigger: getCoderProvider() throwing during its body or static initialization; the method being non-public or instance-level despite the name; the CoderProvider constructor throwing inside the factory; class initialization failure of the coder class.

Common situations: Coder's static initializer depends on a missing dependency or bad config; factory code throwing NPE on uninitialized state; security manager or module access blocking reflection; partial upgrades where the provider's dependencies are incompatible.

Understand the failure class

Background: "invalid response format", "malformed payload", "missing data field": when an API returns 200 but the response shape is wrong — this error's family across 23 libraries.

Related errors

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/ab713e71a7c9f6d4. Report an issue: GitHub.