quarkusio/quarkus · error · RuntimeException

Cannot reset file manager

Error message

Cannot reset file manager

What it means

QuarkusFileManager.reset re-applies the compiler context to the existing file manager, including the ANNOTATION_PROCESSOR_PATH location. An IOException there is wrapped in RuntimeException 'Cannot reset file manager'. This happens on live-reload recompilation when the processor path became invalid between compilations.

Solutions

1. Stop dev mode, run mvn clean install, and restart dev mode so paths exist before reset.
2. Ensure annotation-processor paths exist and are writable before triggering recompilation.
3. Avoid running mvn clean concurrently with quarkus:dev; use dev-mode tooling to clean instead.
4. Check disk space / AV interference on the build directory.

Example fix

// before: target/ wiped while dev mode live-reloads -> reset throws
// after: ./mvnw quarkus:dev (restart) instead of mvn clean during dev mode

for (File dir : context.getAnnotationProcessorPaths()) {
    if (!dir.canRead()) throw new IllegalStateException("processor path unreadable before reset: " + dir);
}

try {
    fileManager.reset(context);
} catch (RuntimeException e) {
    if ("Cannot reset file manager".equals(e.getMessage())) {
        Throwable cause = e.getCause();
        log.errorf("Reset failed: %s — recreate processor paths and restart dev mode", cause.getMessage());
        // rebuild project and restart quarkus:dev
    } else throw e;
}

When it happens

Trigger: Calling reset(context) where setLocation(ANNOTATION_PROCESSOR_PATH, context.getAnnotationProcessorPaths()) throws IOException — typically a processor-path directory/JAR vanished or became unusable since construction.

Common situations: mvn clean executed while dev mode is running; antivirus or IDE locks making paths unreadable; quarkusio/quarkus#42908 scenario where processor paths are missing; out-of-disk conditions.

Related errors

• Cannot initialize file manager
• Cannot initialize reloadable file manager
• Cannot reset reloadable file manager
• Unable to parse
• Unable to read the resolved model from

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/e0e176225804908e. Report an issue: GitHub.

Appendix: source

Thrown at core/deployment/src/main/java/io/quarkus/deployment/dev/filesystem/QuarkusFileManager.java:53

    public abstract Iterable<? extends JavaFileObject> getJavaSources(Iterable<? extends File> files);

    public void reset(Context context) {
        try {
            this.fileManager.setLocation(StandardLocation.CLASS_PATH, context.getClassPath());
            this.fileManager.setLocation(StandardLocation.CLASS_OUTPUT, List.of(context.getOutputDirectory()));
            if (context.getGeneratedSourcesDirectory() != null) {
                // Paths might be missing! (see: https://github.com/quarkusio/quarkus/issues/51178)
                ensureDirectory(context.getGeneratedSourcesDirectory());
                this.fileManager.setLocation(StandardLocation.SOURCE_OUTPUT, List.of(context.getGeneratedSourcesDirectory()));
            }
            if (context.getAnnotationProcessorPaths() != null) {
                // Paths might be missing! (see: https://github.com/quarkusio/quarkus/issues/42908)
                ensureDirectories(context.getAnnotationProcessorPaths());
                this.fileManager.setLocation(StandardLocation.ANNOTATION_PROCESSOR_PATH, context.getAnnotationProcessorPaths());
            }
        } catch (IOException e) {
            throw new RuntimeException("Cannot reset file manager", e);
        }
    }

    private void ensureDirectories(Iterable<File> directories) {
        for (File directory : directories) {
            ensureDirectory(directory);
        }
    }

    private void ensureDirectory(File directory) {
        if (!directory.exists()) {
            if (!directory.mkdirs()) {
                throw new RuntimeException("Cannot create directory " + directory);
            }
        }
    }

    @Override

View on GitHub (pinned to e1c734241f)