skylot/jadx · error · RuntimeException

Failed to read bytes for entry: {}

Error message

Failed to read bytes for entry: {}

What it means

Thrown by the fallback zip parser (Java built-in ZipFile based) when fully reading an entry's decompressed bytes fails. getBytes() wraps the underlying InputStream in a LimitedInputStream and calls readAllBytes(); any IOException/DataFormatException/IllegalStateException from opening the stream, the read, or the size guard is caught and rethrown as a RuntimeException that names the offending entry. The original cause is attached so the real failure (CRC error, truncation, encryption) is inspectable via getCause().

Source

Thrown at jadx-commons/jadx-zip/src/main/java/jadx/zip/fallback/FallbackZipParser.java:78

			return new ZipContent(this, list);
		} catch (Exception e) {
			throw new FallbackException("Error opening zip file: " + file.getAbsolutePath(), e);
		}
	}

	private boolean isValidEntry(IZipEntry zipEntry) {
		boolean validEntry = zipSecurity.isValidEntry(zipEntry);
		if (!validEntry) {
			LOG.warn("Zip entry '{}' is invalid and excluded from processing", zipEntry);
		}
		return validEntry;
	}

	public byte[] getBytes(FallbackZipEntry entry) {
		try (InputStream is = getEntryStream(entry)) {
			return is.readAllBytes();
		} catch (Exception e) {
			throw new RuntimeException("Failed to read bytes for entry: " + entry.getName(), e);
		}
	}

	public InputStream getInputStream(FallbackZipEntry entry) {
		try {
			return getEntryStream(entry);
		} catch (Exception e) {
			throw new RuntimeException("Failed to open input stream for entry: " + entry.getName(), e);
		}
	}

	private InputStream getEntryStream(FallbackZipEntry entry) throws IOException {
		InputStream entryStream = zipFile.getInputStream(entry.getZipEntry());
		InputStream stream;
		if (useLimitedDataStream) {
			stream = new LimitedInputStream(entryStream, entry.getUncompressedSize());
		} else {
			stream = entryStream;

View on GitHub (pinned to e738a26571)

Solutions

1. Inspect getCause() on the thrown RuntimeException to identify whether it is CRC failure, truncation, the read-limit guard (LimitedInputStream), or a decrypt error.
2. If the cause is a read-limit or size mismatch, treat the archive as untrusted/suspect and re-acquire it from a trusted source.
3. If the cause is encryption, jadx does not support decrypting protected entries; supply an unencrypted archive or skip the entry.
4. Wrap the call in a try/catch and skip the failing entry so the rest of the archive still processes.

Example fix

// before
byte[] data = entry.getBytes();
process(data);

// after
byte[] data;
try {
    data = entry.getBytes();
} catch (RuntimeException e) {
    LOG.warn("Skipping unreadable entry {}: {}", entry.getName(), e.getCause());
    continue;
}
process(data);

// Pre-validate the entry is readable by checking the underlying zip is still open
// and the entry is not encrypted. There is no cheap 'canRead' probe, so validate
// what you can:
if (zipEntry.isDirectory()) {
    return; // directories have no bytes
}

try {
    byte[] data = zipEntry.getBytes();
} catch (RuntimeException e) {
    Throwable cause = e.getCause(); // IOException, DataFormatException, IllegalStateException
    LOG.warn("Skipping entry {}: {}", zipEntry.getName(), cause);
    continue;
}

When it happens

Trigger: Calling IZipEntry.getBytes() / FallbackZipParser.getBytes() on a FallbackZipEntry whose underlying ZipFile.getInputStream() throws, or whose readAllBytes() hits an IOException, or whose LimitedInputStream trips the read-limit guard. This code path runs when the custom JadxZipParser could not handle the archive and jadx switched to the fallback parser.

Common situations: A corrupted or truncated APK/JAR/WAR where the central directory points at damaged compressed data; an entry that was partially written during an interrupted build; a crafted zip with a deliberately small declared uncompressed size; an encrypted entry the standard ZipFile cannot decrypt; disk I/O errors on the temp file holding the archive.

Related errors

• Failed to open input stream for entry: {}
• Failed to open zip: {}, error: {}
• Fallback parser failed to open file: {}
• Failed to open zip file: ${file.getAbsolutePath()}
• {}

AI-assisted analysis of skylot/jadx@e738a26571 (2026-08-14). Data as JSON: /api/errors/7337ce32e25e78eb. Report an issue: GitHub.