apache/cassandra · error · ConfigurationException

Unknown compression options () since no compression class fo

Error message

Unknown compression options () since no compression class found

What it means

In createCompressor, if no compression class was resolved (compressorClass == null) yet leftover compression options remain, Cassandra throws ConfigurationException 'Unknown compression options (...) since no compression class found' — the options cannot be interpreted without a class.

Source

Thrown at src/java/org/apache/cassandra/schema/CompressionParams.java:329

        className = className.contains(".") ? className : "org.apache.cassandra.io.compress." + className;
        try
        {
            return FBUtilities.classForNameWithoutInitialization(className, "compression", ICompressor.class);
        }
        catch (ConfigurationException e)
        {
            if (e.getCause() instanceof ClassNotFoundException || e.getCause() instanceof NoClassDefFoundError)
                throw new ConfigurationException("Could not create Compression for type " + className, e);
            throw e;
        }
    }

    private static ICompressor createCompressor(Class<? extends ICompressor> compressorClass, Map<String, String> compressionOptions) throws ConfigurationException
    {
        if (compressorClass == null)
        {
            if (!compressionOptions.isEmpty())
                throw new ConfigurationException("Unknown compression options (" + compressionOptions.keySet() + ") since no compression class found");
            return null;
        }

        return registry.getCompressor(compressorClass, compressionOptions);
    }

    public static ICompressor createCompressor(ParameterizedClass compression) throws ConfigurationException
    {
        return createCompressor(parseCompressorClass(compression.class_name), copyOptions(compression.parameters));
    }

    private static Map<String, String> copyOptions(Map<? extends CharSequence, ? extends CharSequence> co)
    {
        if (co == null || co.isEmpty())
            return Collections.emptyMap();

        Map<String, String> compressionOptions = new HashMap<>();
        for (Map.Entry<? extends CharSequence, ? extends CharSequence> entry : co.entrySet())

View on GitHub (pinned to 88fd0f6a0e)

Solutions

Ensure the map contains a valid 'class' key naming a known ICompressor implementation
Remove unknown/stale keys from the compression options map
Fix key-name typos so the class is actually recognized

Example fix

// before
compression = {'compression_class': 'LZ4Compressor', 'chunk_length_in_kb': '16'}
// after
compression = {'class': 'LZ4Compressor', 'chunk_length_in_kb': '16'}

Defensive patterns

Strategy: validation

Validate before calling

if (!opts.containsKey("class") && opts.size() > 0)
    throw new IllegalArgumentException("Compression options given without a 'class' key: " + opts.keySet());

Try / catch

try { compressionParams = CompressionParams.fromMap(opts); } catch (ConfigurationException e) { if (e.getMessage().contains("since no compression class found")) { /* fix class key name */ } throw e; }

Prevention

Check the exact key name is 'class' (not class_name/compression_class)
Strip unknown keys from compression maps before submission
Keep a whitelist of allowed compression sub-options in tooling

When it happens

Trigger: A compression options map containing unrecognized keys but no resolvable 'class'; calling createCompressor with a null class and non-empty compressionOptions.

Common situations: Misspelled 'class' key (e.g. 'compression_class') so the class lookup yields null while other keys remain; merged maps from configs that dropped the class entry.

Understand the failure class

Background: "Must pass :limit option" / "Missing required option" — required option errors explained — this error's family across 41 libraries.

Related errors

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/a899e458274b01af. Report an issue: GitHub.