quarkusio/quarkus · error · UncheckedIOException

Unable to read entry: ${configFileName} from jar: ${jarFile}

Error message

Unable to read entry: ${configFileName} from jar: ${jarFile}

What it means

Thrown as an UncheckedIOException when the AOT serializer cannot open or read an application config file entry (application.properties / application.yaml style resources) inside a jar during serialization. Signals a corrupt jar, an entry that vanished, or a closed/invalid zip file.

Source

Thrown at independent-projects/bootstrap/runner/src/main/java/io/quarkus/bootstrap/runner/AotSerializedApplication.java:283

        public Map<String, List<ApplicationConfigEntry>> getApplicationConfigFiles() {
            return applicationConfigFiles;
        }

        @Override
        public void visitJarFileEntry(JarFile jarFile, ZipEntry fileEntry) {
            if (!AotRunnerClassLoader.isApplicationConfigFile(fileEntry.getName())) {
                return;
            }

            String configFileName = fileEntry.getName();

            try (var is = jarFile.getInputStream(fileEntry)) {
                String jarName = Paths.get(jarFile.getName()).getFileName().toString();
                applicationConfigFiles.computeIfAbsent(configFileName, k -> new ArrayList<>())
                        .add(new ApplicationConfigEntry(jarName + "!/" + configFileName, is.readAllBytes()));
            } catch (IOException e) {
                throw new UncheckedIOException("Unable to read entry: " + configFileName + " from jar: " + jarFile, e);
            }
        }

        @Override
        public void visitRegularFile(Path jar, Path file, String relativePath) {
            if (!AotRunnerClassLoader.isApplicationConfigFile(relativePath)) {
                return;
            }

            try {
                String jarName = jar.getFileName().toString();
                applicationConfigFiles.computeIfAbsent(relativePath, k -> new ArrayList<>())
                        .add(new ApplicationConfigEntry(jarName + "!/" + relativePath, Files.readAllBytes(file)));
            } catch (IOException e) {
                throw new UncheckedIOException("Unable to read file: " + relativePath, e);
            }
        }
    }

View on GitHub (pinned to e1c734241f)

Solutions

1. Rebuild or re-download the offending jar (mvn clean package) — corruption is the usual cause.
2. Verify jar integrity: jar tf <jarFile> or unzip -t; replace any jar that fails.
3. Ensure no process rebuilds/copies the lib directory while the application is starting or being serialized.
4. Check free disk space and complete file transfers before launching.

Example fix

// before
mvn package
// after
mvn clean package && unzip -t target/quarkus-app/lib/*.jar  # verify each jar opens

for (Path jar : libs) {
  if (!Files.isReadable(jar)) throw new IllegalStateException("unreadable jar: " + jar);
  try (var zf = new java.util.zip.ZipFile(jar.toFile())) { if (zf.getEntry(configFileName) == null) log.warn("missing entry " + configFileName); }
}

boolean isValidJar(Path p) { try (var zf = new java.util.zip.ZipFile(p.toFile())) { return zf.size() >= 0; } catch (Exception e) { return false; } }

try { app.start(); } catch (UncheckedIOException e) { if (e.getMessage().contains("Unable to read entry")) { log.error("Corrupt jar detected: {}", e.getMessage(), e); throw new IllegalStateException("Redeploy application — corrupt jar", e); } throw e; }

When it happens

Trigger: visitJarFileEntry calls jarFile.getInputStream(fileEntry) or is.readAllBytes() for an isApplicationConfigFile entry and an IOException occurs — typically a truncated or corrupted jar in the lib directory.

Common situations: Interrupted/incomplete download or copy of an application jar; disk-full during packaging; jar rebuilt (entries invalidated) while the app is serializing; running from a partially-updated lib/ directory.

Related errors

• Unable to read entry: ${fileEntry.getName()} from jar: ${jar
• Failed to read zip entry ${res}
• Failed to process
• Failed to read
• Failed to open ${jarResource.jarPath}

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/0754140c56456dd7. Report an issue: GitHub.