{"record":{"id":"bc3e8c463391aef7","repo":"java-native-access/jna","slug":"no-method-method-getname-with-signature-sig-in-cls","errorCode":null,"errorMessage":"No method method.getName() with signature sig in cls","messagePattern":"No method method\\.getName\\(\\) with signature sig in cls","errorType":"exception","errorClass":"java.lang.UnsatisfiedLinkError","httpStatus":null,"severity":"error","filePath":"src/com/sun/jna/Native.java","lineNumber":2019,"sourceCode":"                if (LastErrorException.class.isAssignableFrom(etypes[e])) {\n                    throwLastError = true;\n                    break;\n                }\n            }\n\n            Function f = lib.getFunction(method.getName(), method);\n            try {\n                handles[i] = registerMethod(cls, method.getName(),\n                                            sig, cvt,\n                                            closure_atypes, atypes, rcvt,\n                                            closure_rtype, rtype,\n                                            method,\n                                            f.peer, f.getCallingConvention(),\n                                            throwLastError,\n                                            toNative, fromNative,\n                                            f.encoding);\n            } catch(NoSuchMethodError e) {\n                throw new UnsatisfiedLinkError(\"No method \" + method.getName() + \" with signature \" + sig + \" in \" + cls);\n            }\n        }\n        synchronized(registeredClasses) {\n            registeredClasses.put(cls, handles);\n            registeredLibraries.put(cls, lib);\n        }\n    }\n\n    /**\n     * Get the {@link NativeLibrary} instance that is wrapped by the given\n     * {@link Library} interface instance.\n     *\n     * @param library the {@link Library} interface instance, which was created\n     * by the {@link Native#load Native.load()} method\n     * @return the wrapped {@link NativeLibrary} instance\n     */\n    public static NativeLibrary getNativeLibrary(final Library library) {\n        if(library == null) {","sourceCodeStart":2001,"sourceCodeEnd":2037,"githubUrl":"https://github.com/java-native-access/jna/blob/d036ad9781adad4b66693e8fa7098e4ac665e0a3/src/com/sun/jna/Native.java#L2001-L2037","documentation":"JNA throws this UnsatisfiedLinkError when the native library was loaded but does not export a function matching the Java method's name and JNI-style signature. The Java side registered the method, but the native symbol lookup or signature match failed inside the native dispatcher.","triggerScenarios":"Calling a method on a registered (Native.register direct-mapping) class whose native library lacks a function of that name/arity, or whose argument signature does not match what JNA derived.","commonSituations":"Version mismatch between the .so/.dll and the Java interface (function renamed or added later); wrong library mapped to the class; typos or case-sensitivity on Linux; method overloads producing a signature the native side lacks.","solutions":["Verify the native library actually exports the function (nm -D libfoo.so / dumpbin /exports) with the exact name.","Check that the register()/load() call binds the correct library file and version.","Align the Java method signature (types and arity) with the native function; use A or _A name mapping only if the native symbol is mangled/annotated.","Rebuild or redeploy the native library so it matches the Java interface."],"exampleFix":"// before: Java expects foo(int) but native exports only foo_long\nnative long foo(int x);\n// after: match the actual export\nnative long foo(long x);","handlingStrategy":"try-catch","validationCode":"// Verify the symbol exists before binding (Unix)\nProcess p = new ProcessBuilder(\"sh\", \"-c\",\n    \"nm -D \" + libPath + \" | grep -w \" + functionName).start();\nif (p.waitFor() != 0) throw new IllegalStateException(\n    functionName + \" missing from \" + libPath);","typeGuard":null,"tryCatchPattern":"try {\n    result = myNative.compute(x);\n} catch (UnsatisfiedLinkError e) {\n    if (e.getMessage().startsWith(\"No method \")) {\n        LOG.error(\"Native function missing or signature mismatch: {}\", e.getMessage());\n        throw new NativeBindingException(\"Library version mismatch\", e);\n    }\n    throw e;\n}","preventionTips":["Pin and verify the native library version alongside the Java interface jar.","Smoke-test every bound function at startup.","Keep the C header and Java interface in sync (generate bindings when possible).","Check exported symbol names with nm/dumpbin when the library changes."],"tags":["jna","unsatisfied-link","native-symbol","signature-mismatch"],"backgroundTag":"resource-not-found","analyzedSha":"d036ad9781adad4b66693e8fa7098e4ac665e0a3","analyzedAt":"2026-09-12T06:50:59.239Z","contentChangedAt":"2026-09-12T06:50:59.239Z","schemaVersion":2},"datasetVersion":"2026-09-14T05:17:10.506Z"}