apache/beam · error · RuntimeException

Unable to load runtime value.

Error message

Unable to load runtime value.

What it means

RuntimeValueProvider.get() resolves the underlying option value reflectively at runtime; any Throwable raised during that resolution (except OutOfMemoryError, which is rethrown) is wrapped in a RuntimeException("Unable to load runtime value."). This indicates the option getter itself failed, e.g. due to deserialization or option-conversion errors.

Solutions

1. Inspect the wrapped cause (e.getCause()) of the RuntimeException to find the root failure
2. Fix or remove throwing logic in the PipelineOptions getter method backing the provider
3. Ensure driver and worker classpaths/Beam versions match so reflective resolution succeeds

Example fix

// before
String v = options.someComputedValue(); // getter throws internally at runtime
// after
// make the getter pure; catch/repair at definition:
@Implementation... value() { try { return compute(); } catch (Exception e) { return fallback; } }

if (!provider.isAccessible()) throw new IllegalStateException("provider not accessible; cannot load runtime value yet");

try { v = provider.get(); } catch (RuntimeException e) { log.error("runtime value load failed", e.getCause()); v = defaultValue; }

When it happens

Trigger: Calling get() on a RuntimeValueProvider when the underlying getter invocation throws — e.g. the method raises during value computation, the registered options object fails an as(klass) conversion, or reflection/proxy resolution fails.

Common situations: Custom PipelineOptions getters with side effects that throw on the worker, incompatible option types registered at runtime, or classpath differences between driver and worker causing reflective failures.

Understand the failure class

Background: "This is a bug, please report it": internal invariant violations, unreachable panics, and SNH errors explained — this error's family across 47 libraries.

Related errors

• AutoValue builder class
• Can not call prepareRun
• cannot register Coder : does not have an accessible method…
• cannot register Coder : method named 'of' with arguments…
• cannot register Coder : method named 'of' with arguments…

AI-assisted analysis of apache/beam@12126d8942 (2026-09-13). Data as JSON: /api/errors/899937b082609199. Report an issue: GitHub.

Appendix: source

Thrown at sdks/java/core/src/main/java/org/apache/beam/sdk/options/ValueProvider.java:275

      }
      try {
        Method method = klass.getMethod(methodName);
        PipelineOptions methodOptions = options.as(klass);
        InvocationHandler handler = Proxy.getInvocationHandler(methodOptions);
        @SuppressWarnings("unchecked")
        ValueProvider<T> result = (ValueProvider<T>) handler.invoke(methodOptions, method, null);
        // Two cases: If we have deserialized a new value from JSON, it will
        // be wrapped in a StaticValueProvider, which we can provide here. If
        // not, there was no JSON value, and we return the default, whether or
        // not it is null.
        if (result instanceof StaticValueProvider) {
          return result.get();
        }
        return defaultValue;
      } catch (OutOfMemoryError oom) {
        throw oom;
      } catch (Throwable e) {
        throw new RuntimeException("Unable to load runtime value.", e);
      }
    }

    @Override
    public boolean isAccessible() {
      return optionsMap.get(optionsId) != null;
    }

    /** Returns the property name that corresponds to this provider. */
    public String propertyName() {
      return propertyName;
    }

    @Override
    public String toString() {
      if (isAccessible()) {
        return String.valueOf(get());
      }

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