{"record":{"id":"7d46c8fedd5773f2","repo":"apereo/cas","slug":"target-class-does-not-implement-possible-cach","errorCode":null,"errorMessage":"Target class [{}] does not implement possible cacheable method [{}].","messagePattern":"Target class \\[(.+?)\\] does not implement possible cacheable method \\[(.+?)\\]\\.","errorType":"console","errorClass":null,"httpStatus":null,"severity":"warning","filePath":"support/cas-server-support-person-directory-core/src/main/java/org/apereo/cas/persondir/cache/AttributeBasedCacheKeyGenerator.java","lineNumber":189,"sourceCode":"    /**\n     * Iterates over the {@link CacheableMethod} instances to determine which instance the\n     * passed {@link MethodInvocation} applies to.\n     *\n     * @param methodInvocation method invocation\n     * @return Cacheable method\n     */\n    protected CacheableMethod resolveCacheableMethod(final MethodInvocation methodInvocation) {\n        val targetMethod = methodInvocation.getMethod();\n        val targetClass = targetMethod.getDeclaringClass();\n\n        for (val method : CacheableMethod.values()) {\n            Method cacheableMethod = null;\n            try {\n                cacheableMethod = targetClass.getMethod(method.getName(), method.getArgs());\n            } catch (final SecurityException e) {\n                LOGGER.warn(\"Security exception while attempting to if the target class [{}] implements the cacheable method [{}]\", targetClass, cacheableMethod, e);\n            } catch (final NoSuchMethodException e) {\n                LOGGER.warn(\"Target class [{}] does not implement possible cacheable method [{}].\", targetClass, cacheableMethod);\n            }\n            if (targetMethod.equals(cacheableMethod)) {\n                return method;\n            }\n        }\n        throw new IllegalArgumentException(\"Do not know how to generate a cache entry for \" + targetMethod + \" on class \" + targetClass);\n    }\n}\n","sourceCodeStart":171,"sourceCodeEnd":198,"githubUrl":"https://github.com/apereo/cas/blob/e7288fc434b4f4505b8452e1a57e8fb3111bb863/support/cas-server-support-person-directory-core/src/main/java/org/apereo/cas/persondir/cache/AttributeBasedCacheKeyGenerator.java#L171-L198","documentation":"AttributeBasedCacheKeyGenerator.resolveCacheableMethod iterates all known CacheableMethod values and, if none of the reflective lookups produce a method equal to the target method, the caller throws IllegalArgumentException 'Do not know how to generate a cache entry'. The warn message itself is logged when the target class simply does not implement a candidate cacheable method — normal probing noise.","triggerScenarios":"Class.getMethod throws NoSuchMethodException for a CacheableMethod candidate the class doesn't implement (expected path); the fatal case is the trailing throw new IllegalArgumentException when targetMethod matches no known cacheable method.","commonSituations":"Passing a custom or newly added DAO method to the cache-key generator that predates the CacheableMethod enum; version drift between person-directory-core and a custom implementation overriding a method the generator doesn't recognize.","solutions":["Upgrade person-directory-core / CAS so the CacheableMethod enum covers the target method","Restrict caching to the supported attribute-repository DAO implementations","Register a custom CacheKeyGenerator that handles your custom method","Do not wrap custom PersonAttributeDao methods around the attribute-based cache"],"exampleFix":"// before\ncustomDao = new MyCustomPersonAttributeDao(); // passed to CachingPersonAttributeDaoImpl cache\n// after\nwrappedDao = new CachingPersonAttributeDaoImpl();\nwrappedDao.setCacheManager(...);\nwrappedDao.setPersonAttributeDao(new DefaultPersonAttributeDao(...)); // supported target only","handlingStrategy":"fallback","validationCode":"boolean isKnownCacheableTarget(Class<?> target, Method m) {\n    return Arrays.stream(CacheableMethod.values())\n        .anyMatch(cm -> {\n            try { return m.equals(target.getMethod(cm.getName(), cm.getArgs())); }\n            catch (Exception e) { return false; }\n        });\n}","typeGuard":null,"tryCatchPattern":"try { return keyGenerator.generate(target, method); }\ncatch (IllegalArgumentException e) {\n    log.warn(\"Falling back to default cache key\", e);\n    return method.toGenericString();\n}","preventionTips":["Only wrap supported DAO implementations with the attribute-based cache","On upgrade, re-check that custom methods are still covered by CacheableMethod","Add a smoke test exercising cache-key generation at startup"],"tags":["reflection","cache","unsupported-operation"],"backgroundTag":"unsupported-operation","analyzedSha":"e7288fc434b4f4505b8452e1a57e8fb3111bb863","analyzedAt":"2026-09-08T15:39:16.015Z","contentChangedAt":"2026-09-08T15:39:16.015Z","schemaVersion":2},"datasetVersion":"2026-09-15T23:17:13.987Z"}