{"record":{"id":"8027a2c65f34c66b","repo":"karatelabs/karate","slug":"failed-to-create-resource-from-url-url","errorCode":null,"errorMessage":"Failed to create resource from URL: {url}","messagePattern":"Failed to create resource from URL: (.+?)","errorType":"exception","errorClass":"RuntimeException","httpStatus":null,"severity":"error","filePath":"karate-js/src/main/java/io/karatelabs/common/Resource.java","lineNumber":869,"sourceCode":"                byte[] bytes = FileUtils.toBytes(is);\n                return root != null ? new UrlResource(url, bytes, root) : new UrlResource(url, bytes);\n            } catch (Exception e) {\n                throw new RuntimeException(\"Failed to fetch content from URL: \" + url, e);\n            }\n        }\n\n        // Handle file:// and jar:// URLs\n        try {\n            Path path = urlToPath(url, root);\n            return root != null ? new PathResource(path, root) : new PathResource(path);\n        } catch (java.nio.file.ProviderNotFoundException e) {\n            // JAR file system provider not available (common in jpackage/JavaFX apps)\n            // Fall back to streaming the resource content\n            try (java.io.InputStream is = url.openStream()) {\n                String content = FileUtils.toString(is);\n                return root != null ? new MemoryResource(content, root) : new MemoryResource(content);\n            } catch (Exception ex) {\n                throw new RuntimeException(\"Failed to create resource from URL: \" + url, ex);\n            }\n        } catch (Exception e) {\n            throw new RuntimeException(\"Failed to create resource from URL: \" + url, e);\n        }\n    }\n\n}\n","sourceCodeStart":851,"sourceCodeEnd":877,"githubUrl":"https://github.com/karatelabs/karate/blob/a22eb90246d958d15a47bf436693d0121ad2812d/karate-js/src/main/java/io/karatelabs/common/Resource.java#L851-L877","documentation":"Thrown from the fallback branch of the URL resource factory: when a jar: URL cannot be mounted through the JAR filesystem provider, the code streams the entry content into a MemoryResource instead; if even that openStream/read fails, this error is thrown naming the URL.","triggerScenarios":"Loading a resource from inside a jar/zip URL where the JAR filesystem provider is unavailable (e.g. jpackage/JavaFX packaged apps) AND url.openStream() or reading the content also throws — typically the jar entry does not exist or the jar file is unreadable/corrupt.","commonSituations":"jpackage-packaged desktop apps where the NIO zipfs provider is missing; the referenced jar was moved, deleted, or rebuilt; the entry path inside the jar has wrong casing; shaded jars missing the resource.","solutions":["Verify the jar file exists and the entry path is correct: 'unzip -l app.jar' and compare the entry path exactly (case-sensitive)","Inspect the cause chain (ex) to see whether the entry is missing vs a read failure","Rebuild/redeploy the jar so it actually contains the resource","If running under jpackage, add the zip filesystem module or ship the resource outside the jar and reference it by file path"],"exampleFix":"// before\nResource r = Resource.fromUrl(new URL(\"jar:file:/app/lib/rules.jar!/rules/discount.js\"));\n// after\ntry {\n    Resource r = Resource.fromUrl(new URL(jarUrl));\n} catch (RuntimeException e) {\n    // fallback: unpack once at startup and use a file resource\n    Resource r = Resource.fromFilePath(\"/app/exploded/rules/discount.js\");\n}","handlingStrategy":"try-catch","validationCode":"// verify the jar entry exists before loading\njava.util.zip.ZipFile zip = new java.util.zip.ZipFile(\"/app/lib/rules.jar\");\nif (zip.getEntry(\"rules/discount.js\") == null) {\n    throw new IllegalStateException(\"entry missing from jar\");\n}","typeGuard":null,"tryCatchPattern":"try {\n    Resource r = Resource.fromUrl(jarUrl);\n} catch (RuntimeException e) {\n    // cause chain: streaming failure inside the zipfs fallback\n    throw new IllegalStateException(\"jar resource unusable: \" + jarUrl, e.getCause());\n}","preventionTips":["List jar contents ('unzip -l') to confirm entry paths and casing","Ship resources outside the jar in jpackage/JavaFX deployments","Keep entry paths ASCII and lowercase to avoid casing bugs","Rebuild and redeploy jars after adding resources"],"tags":["jar","resource-loading","classpath"],"backgroundTag":"file-read-failed","analyzedSha":"a22eb90246d958d15a47bf436693d0121ad2812d","analyzedAt":"2026-09-12T09:01:00.220Z","contentChangedAt":"2026-09-12T09:01:00.220Z","schemaVersion":2},"datasetVersion":"2026-09-16T19:17:19.609Z"}