{"record":{"id":"1981ff5aa54881b3","repo":"apache/maven","slug":"key-should-not-contain-a-type-variable","errorCode":null,"errorMessage":"Key should not contain a type variable: {}","messagePattern":"Key should not contain a type variable: (.+?)","errorType":"exception","errorClass":"IllegalArgumentException","httpStatus":null,"severity":"error","filePath":"impl/maven-di/src/main/java/org/apache/maven/di/impl/Types.java","lineNumber":325,"sourceCode":"        }\n\n        if (original instanceof ParameterizedType parameterizedType) {\n            Type[] typeArguments = parameterizedType.getActualTypeArguments();\n            Type[] repackedTypeArguments = simplifyTypes(typeArguments);\n\n            if (isAllObjects(repackedTypeArguments)) {\n                return parameterizedType.getRawType();\n            }\n\n            if (typeArguments != repackedTypeArguments) {\n                return parameterizedType(\n                        parameterizedType.getOwnerType(), parameterizedType.getRawType(), repackedTypeArguments);\n            }\n            return original;\n        }\n\n        if (original instanceof TypeVariable) {\n            throw new IllegalArgumentException(\"Key should not contain a type variable: \" + original);\n        }\n\n        if (original instanceof WildcardType wildcardType) {\n            Type[] upperBounds = wildcardType.getUpperBounds();\n            if (upperBounds.length == 1) {\n                Type upperBound = upperBounds[0];\n                if (upperBound != Object.class) {\n                    return simplifyType(upperBound);\n                }\n            } else if (upperBounds.length > 1) {\n                throw new IllegalArgumentException(\"Multiple upper bounds not supported: \" + original);\n            }\n\n            Type[] lowerBounds = wildcardType.getLowerBounds();\n            if (lowerBounds.length == 1) {\n                return simplifyType(lowerBounds[0]);\n            } else if (lowerBounds.length > 1) {\n                throw new IllegalArgumentException(\"Multiple lower bounds not supported: \" + original);","sourceCodeStart":307,"sourceCodeEnd":343,"githubUrl":"https://github.com/apache/maven/blob/e4093d4e120eac99d6bdce5ba67cace2f3085c97/impl/maven-di/src/main/java/org/apache/maven/di/impl/Types.java#L307-L343","documentation":"Error \"Key should not contain a type variable: {}\" thrown in apache/maven.","triggerScenarios":"Thrown at impl/maven-di/src/main/java/org/apache/maven/di/impl/Types.java:325 when the library encounters an invalid state.","commonSituations":"See trigger scenarios.","solutions":[],"exampleFix":null,"handlingStrategy":null,"validationCode":null,"typeGuard":null,"tryCatchPattern":null,"preventionTips":[],"tags":[],"backgroundTag":null,"analyzedSha":"e4093d4e120eac99d6bdce5ba67cace2f3085c97","analyzedAt":"2026-08-21T22:58:24.034Z","schemaVersion":2},"datasetVersion":"2026-08-21T23:17:16.201Z"}