{"record":{"id":"40625228f5f5a3dc","repo":"apache/flink","slug":"join-hint-must-not-be-null","errorCode":null,"errorMessage":"Join Hint must not be null.","messagePattern":"Join Hint must not be null\\.","errorType":"exception","errorClass":"IllegalArgumentException","httpStatus":null,"severity":"error","filePath":"flink-core/src/main/java/org/apache/flink/api/common/operators/base/JoinOperatorBase.java","lineNumber":114,"sourceCode":"            BinaryOperatorInformation<IN1, IN2, OUT> operatorInfo,\n            int[] keyPositions1,\n            int[] keyPositions2,\n            String name) {\n        super(new UserCodeObjectWrapper<>(udf), operatorInfo, keyPositions1, keyPositions2, name);\n    }\n\n    public JoinOperatorBase(\n            Class<? extends FT> udf,\n            BinaryOperatorInformation<IN1, IN2, OUT> operatorInfo,\n            int[] keyPositions1,\n            int[] keyPositions2,\n            String name) {\n        super(new UserCodeClassWrapper<>(udf), operatorInfo, keyPositions1, keyPositions2, name);\n    }\n\n    public void setJoinHint(JoinHint joinHint) {\n        if (joinHint == null) {\n            throw new IllegalArgumentException(\"Join Hint must not be null.\");\n        }\n        this.joinHint = joinHint;\n    }\n\n    public JoinHint getJoinHint() {\n        return joinHint;\n    }\n\n    public void setCustomPartitioner(Partitioner<?> partitioner) {\n        this.partitioner = partitioner;\n    }\n\n    public Partitioner<?> getCustomPartitioner() {\n        return partitioner;\n    }\n}\n","sourceCodeStart":96,"sourceCodeEnd":131,"githubUrl":"https://github.com/apache/flink/blob/2f3c205e9266cb30240eb7f4fdab15cad629a70f/flink-core/src/main/java/org/apache/flink/api/common/operators/base/JoinOperatorBase.java#L96-L131","documentation":"Thrown by JoinOperatorBase.setJoinHint when a caller passes null as the join hint. Hints are not optional at this level; the setter validates non-nullness before assigning, so callers must pass an explicit JoinHint (use JoinHint.OPTIMIZER_CHOOSES when no specific hint is desired).","triggerScenarios":"Triggered at runtime when the operation fails because: Join Hint must not be null.","commonSituations":"Commonly caused by misconfiguration, missing dependencies or files, unsupported types or operations, or invalid user input leading to: Join Hint must not be null.","solutions":["Address the cause reported by the error message: Join Hint must not be null.","Verify the inputs, configuration values, and classpath/dependency setup related to this operation, then retry."],"exampleFix":"Correct the condition described (\"Join Hint must not be null.\") and rerun the job or command.","handlingStrategy":"validation","validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"2f3c205e9266cb30240eb7f4fdab15cad629a70f","analyzedAt":"2026-08-14T08:48:24.518Z","contentChangedAt":"2026-08-14T08:48:24.518Z","schemaVersion":2},"datasetVersion":"2026-09-23T08:17:48.524Z"}