MuntashirAkon/AppManager · error · FileNotFoundException

Class definition for + node.getFullPath() + is not found.

Error message

Class definition for + node.getFullPath() + is not found.

What it means

ZipFileSystem.getInputStream(node) casts node.getObject() to ZipEntry. If the node holds no cached ZipEntry (null), it throws FileNotFoundException("Class definition for <path> is not found."). The message is misleading — it actually means the zip entry object for that node was never populated or was dropped from cache.

Solutions

1. Refresh/re-scan the ZipFileSystem so nodes get their ZipEntry objects attached before reading.
2. Obtain the node from the live ZipFileSystem instance rather than a stale snapshot.
3. Verify node.getObject() instanceof ZipEntry before calling getInputStream.
4. Catch FileNotFoundException and reopen the archive to rebuild the entry index.

Example fix

// before
InputStream in = zipFs.getInputStream(staleNode);
// after
zipFs.refresh();
Node<?> node = zipFs.getNode(staleNode.getFullPath());
if (node != null && node.getObject() instanceof ZipEntry) {
    InputStream in = zipFs.getInputStream(node);
}

if (!(node.getObject() instanceof ZipEntry)) { zipFs.refresh(); node = zipFs.getNode(node.getFullPath()); }

boolean hasZipEntry(Node<?> n) { return n.getObject() instanceof ZipEntry; }

try { return zipFs.getInputStream(node); } catch (FileNotFoundException e) { zipFs.refresh(); return zipFs.getInputStream(zipFs.getNode(node.getFullPath())); }

When it happens

Trigger: Reading a stream for a ZIP node whose getObject() is null — typically when cacheFile() is called for a node that was not previously scanned into the zip entry index, or the entry list was rebuilt and the node's ZipEntry reference was lost.

Common situations: Extracting a file from a ZIP whose entry table was re-scanned; using a Node from a stale filesystem snapshot after the archive was modified; subclasses whose scan didn't attach ZipEntry objects to nodes; large archives where entry objects are lazily loaded.

Understand the failure class

Background: "Not found" and "does not exist" errors: why "Task not found", "No such folder", and "Can't find" fire when a lookup comes back empty — this error's family across 14 libraries.

Related errors

• already exists.
• APPEND + TRUNCATE not allowed
• Backup failed for
• Backup failed for
• Bad mode: + mode

AI-assisted analysis of MuntashirAkon/AppManager@0152f468fc (2026-09-12). Data as JSON: /api/errors/1982a51173e5126b. Report an issue: GitHub.

Appendix: source

Thrown at app/src/main/java/io/github/muntashirakon/io/fs/ZipFileSystem.java:342

        if (access == OsConstants.R_OK) {
            return true;
        }
        if (access == OsConstants.W_OK) {
            return Objects.requireNonNull(getOptions()).readWrite;
        }
        if (access == (OsConstants.R_OK | OsConstants.W_OK)) {
            return Objects.requireNonNull(getOptions()).readWrite;
        }
        // X_OK, R_OK|X_OK, R_OK|W_OK|X_OK are false
        return false;
    }

    @NonNull
    @Override
    protected InputStream getInputStream(@NonNull Node<?> node) throws IOException {
        ZipEntry zipEntry = (ZipEntry) node.getObject();
        if (zipEntry == null) {
            throw new FileNotFoundException("Class definition for " + node.getFullPath() + " is not found.");
        }
        return Objects.requireNonNull(mZipFile).getInputStream(zipEntry);
    }

    @Override
    protected void cacheFile(@NonNull Node<?> src, @NonNull File sink) throws IOException {
        try (InputStream is = getInputStream(src);
             FileOutputStream os = new FileOutputStream(sink)) {
            IoUtils.copy(is, os);
        }
    }

    @NonNull
    private static Node<ZipEntry> buildTree(@NonNull ZipFile zipFile) {
        Node<ZipEntry> rootNode = new Node<>(null, File.separator);
        Enumeration<? extends ZipEntry> zipEntries = zipFile.entries();
        while (zipEntries.hasMoreElements()) {
            ZipEntry zipEntry = zipEntries.nextElement();

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