{"record":{"id":"87c8ea328eb85960","repo":"apache/beam","slug":"unknown-accumulation-mode-accumulationmode","errorCode":null,"errorMessage":"Unknown accumulation mode [${accumulationMode}]","messagePattern":"Unknown accumulation mode \\[(.+?)\\]","errorType":"validation","errorClass":"IllegalArgumentException","httpStatus":null,"severity":"error","filePath":"sdks/java/extensions/euphoria/src/main/java/org/apache/beam/sdk/extensions/euphoria/core/client/operator/WindowBuilder.java","lineNumber":93,"sourceCode":"  }\n\n  @Override\n  public WindowBuilder<T> triggeredBy(Trigger trigger) {\n    window = requireNonNull(window).triggering(trigger);\n    return this;\n  }\n\n  @Override\n  public WindowBuilder<T> accumulationMode(WindowingStrategy.AccumulationMode accumulationMode) {\n    switch (requireNonNull(accumulationMode)) {\n      case DISCARDING_FIRED_PANES:\n        window = requireNonNull(window).discardingFiredPanes();\n        break;\n      case ACCUMULATING_FIRED_PANES:\n        window = requireNonNull(window).accumulatingFiredPanes();\n        break;\n      default:\n        throw new IllegalArgumentException(\"Unknown accumulation mode [\" + accumulationMode + \"]\");\n    }\n    return this;\n  }\n\n  @Override\n  public WindowBuilder<T> withAllowedLateness(Duration allowedLateness) {\n    window = requireNonNull(window).withAllowedLateness(requireNonNull(allowedLateness));\n    return this;\n  }\n\n  @Override\n  public WindowBuilder<T> withAllowedLateness(\n      Duration allowedLateness, Window.ClosingBehavior closingBehavior) {\n    window =\n        requireNonNull(window)\n            .withAllowedLateness(requireNonNull(allowedLateness), requireNonNull(closingBehavior));\n    return this;\n  }","sourceCodeStart":75,"sourceCodeEnd":111,"githubUrl":"https://github.com/apache/beam/blob/12126d8942aaf848030c478b4c6a28c6af861c66/sdks/java/extensions/euphoria/src/main/java/org/apache/beam/sdk/extensions/euphoria/core/client/operator/WindowBuilder.java#L75-L111","documentation":"WindowBuilder.accumulationMode() maps an AccumulationMode enum to the corresponding Beam windowing behavior (discarding/accumulating fired panes). An unrecognized mode hits the default branch and throws IllegalArgumentException listing the unsupported mode.","triggerScenarios":"Calling windowBuilder.accumulationMode(AccumulationMode.X) with a mode not handled by the switch (the code handles DISCARDING_FIRED_PANES, ACCUMULATING_FIRED_PANES, and possibly others; e.g. RETRACTING or UNSPECIFIED-style values fall through), typically inside a Window.into(...).triggering(...).accumulationMode(...) chain.","commonSituations":"Upgrading Beam where AccumulationMode gained new constants while the euphoria WindowBuilder switch wasn't extended; typos/mismatches when porting Flink-style accumulation settings to Beam euphoria.","solutions":["Use only accumulation modes supported by the builder (e.g. ACCUMULATING_FIRED_PANES or the default discarding behavior).","Check the euphoria extension source for the exact set of handled modes at your Beam version.","Upgrade or patch the euphoria extension if a newly added AccumulationMode constant is required."],"exampleFix":"// before\nbuilder.accumulationMode(AccumulationMode.RETRACTING_FIRED_PANES);\n// after\nbuilder.accumulationMode(AccumulationMode.ACCUMULATING_FIRED_PANES);","handlingStrategy":"validation","validationCode":"if (mode != AccumulationMode.DISCARDING_FIRED_PANES\n    && mode != AccumulationMode.ACCUMULATING_FIRED_PANES) {\n  throw new IllegalArgumentException(\"Unsupported accumulation mode: \" + mode);\n}","typeGuard":null,"tryCatchPattern":"try {\n  builder.accumulationMode(mode);\n} catch (IllegalArgumentException e) {\n  builder.accumulationMode(AccumulationMode.ACCUMULATING_FIRED_PANES);\n}","preventionTips":["Only pass modes verified against the euphoria WindowBuilder source for your Beam version.","Pin the Beam version and re-verify enum coverage on upgrades.","Default to DISCARDING/ACCUMULATING fired panes in configuration templates."],"tags":["java","illegal-argument","enum","windowing","euphoria"],"backgroundTag":"invalid-enum-value","analyzedSha":"12126d8942aaf848030c478b4c6a28c6af861c66","analyzedAt":"2026-09-13T01:50:10.254Z","contentChangedAt":"2026-09-13T01:50:10.254Z","schemaVersion":2},"datasetVersion":"2026-09-14T21:17:11.552Z"}