apache/beam · error · IllegalArgumentException

Expected getter for property [%s] to be marked with @%s on a

Error message

Expected getter for property [%s] to be marked with @%s on all %s, found only on %s

What it means

Thrown when a property getter is expected to carry a given annotation (e.g. @Default, @Hidden, @Validation) on every interface that declares it, but the annotation is present on only some declarations. Beam requires annotation consistency across the hierarchy to derive reliable property metadata.

Source

Thrown at sdks/java/core/src/main/java/org/apache/beam/sdk/options/PipelineOptionsFactory.java:1405

            String.format(
                "%n  - Method [%s] has multiple definitions %s",
                errDef.method.getName(), errDef.collidingMethods));
      }
      throw new IllegalArgumentException(errorBuilder.toString());
    }
  }

  private static class InconsistentlyAnnotatedGetters {
    PropertyDescriptor descriptor;
    Iterable<String> getterClassNames;
    Iterable<String> gettersWithTheAnnotationClassNames;
  }

  private static void throwForGettersWithInconsistentAnnotation(
      List<InconsistentlyAnnotatedGetters> getters, Class<? extends Annotation> annotationClass) {
    if (getters.size() == 1) {
      InconsistentlyAnnotatedGetters getter = getters.get(0);
      throw new IllegalArgumentException(
          String.format(
              "Expected getter for property [%s] to be marked with @%s on all %s, "
                  + "found only on %s",
              getter.descriptor.getName(),
              annotationClass.getSimpleName(),
              getter.getterClassNames,
              getter.gettersWithTheAnnotationClassNames));
    } else if (getters.size() > 1) {
      StringBuilder errorBuilder =
          new StringBuilder(
              String.format(
                  "Property getters are inconsistently marked with @%s:",
                  annotationClass.getSimpleName()));
      for (InconsistentlyAnnotatedGetters getter : getters) {
        errorBuilder.append(
            String.format(
                "%n  - Expected for property [%s] to be marked on all %s, " + "found only on %s",
                getter.descriptor.getName(),

View on GitHub (pinned to 12126d8942)

Solutions

Copy the named annotation onto the getter declarations listed as missing it.
Or remove the annotation everywhere so the property is uniformly unannotated.
Search the codebase for all declarations of the getter name and keep them identical.

Example fix

// before
interface A extends PipelineOptions { @Default.String("x") String getFoo(); }
interface B extends A { String getFoo(); }
// after
interface A extends PipelineOptions { @Default.String("x") String getFoo(); }
interface B extends A { @Default.String("x") String getFoo(); }

Defensive patterns

Strategy: validation

Validate before calling

for (java.lang.reflect.Method m : MyOptions.class.getMethods()) {
  if (m.getName().equals("getFoo")) {
    if (m.getAnnotation(org.apache.beam.sdk.options.Default.String.class) == null) {
      throw new IllegalStateException("getFoo in " + m.getDeclaringClass() + " missing @Default.String");
    }
  }
}

Try / catch

try {
  PipelineOptionsFactory.fromArgs(args).as(MyOptions.class);
} catch (IllegalArgumentException e) {
  if (e.getMessage().contains("to be marked with @")) { /* copy the annotation to the listed declarations */ }
  throw e;
}

Prevention

When overriding a getter, copy all its annotations verbatim
Search all declarations of a getter before editing its annotations
Prefer single-declaration inheritance over per-interface re-declaration

When it happens

Trigger: PipelineOptionsFactory registration when throwForGettersWithInconsistentAnnotation finds one InconsistentlyAnnotatedGetters: getFoo() is annotated with e.g. @Default.String in sub-interface A but not in sub-interface B, both contributing the same property.

Common situations: Overriding a getter in a sub-interface without copying its annotation; adding an annotation to a base interface while stale un-annotated overrides exist elsewhere.

Understand the failure class

Background: Conflicting config options: "cannot be used together" — configuration validation errors across open-source libraries — this error's family across 162 libraries.

Related errors

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/4a6ec93d980236a1. Report an issue: GitHub.