conductor-oss/conductor · error · IllegalArgumentException

Connection factory is undefined

Error message

Connection factory is undefined

What it means

Constructor guard on AMQPObservableQueue: the ConnectionFactory argument is null. Thrown during construction before any network activity. The Builder always builds a factory via buildConnectionFactory(), so reaching this guard means the public constructor was used directly with a null factory (typical in tests or custom wiring).

Source

Thrown at amqp/src/main/java/com/netflix/conductor/contribs/queue/amqp/AMQPObservableQueue.java:80

    private final String QUEUE_TYPE = "x-queue-type";
    private final int batchSize;
    private final boolean useExchange;
    private int pollTimeInMS;
    private AMQPConnection amqpConnection;

    protected LinkedBlockingQueue<Message> messages = new LinkedBlockingQueue<>();
    private volatile boolean running;

    public AMQPObservableQueue(
            ConnectionFactory factory,
            Address[] addresses,
            boolean useExchange,
            AMQPSettings settings,
            AMQPRetryPattern retrySettings,
            int batchSize,
            int pollTimeInMS) {
        if (factory == null) {
            throw new IllegalArgumentException("Connection factory is undefined");
        }
        if (addresses == null || addresses.length == 0) {
            throw new IllegalArgumentException("Addresses are undefined");
        }
        if (settings == null) {
            throw new IllegalArgumentException("Settings are undefined");
        }
        if (batchSize <= 0) {
            throw new IllegalArgumentException("Batch size must be greater than 0");
        }
        if (pollTimeInMS <= 0) {
            throw new IllegalArgumentException("Poll time must be greater than 0 ms");
        }
        this.useExchange = useExchange;
        this.settings = settings;
        this.batchSize = batchSize;
        this.amqpConnection = AMQPConnection.getInstance(factory, addresses, retrySettings);
        this.retrySettings = retrySettings;

View on GitHub (pinned to cf7c3e4a8a)

Solutions

1. Construct via AMQPObservableQueue.Builder, which builds the ConnectionFactory from properties.
2. If constructing directly, pass a non-null ConnectionFactory (e.g. new ConnectionFactory()).
3. Add a null-check in the calling code before constructing.

Example fix

// before: direct construction with null factory
new AMQPObservableQueue(null, addresses, useExchange, settings, retry, batchSize, pollTimeInMS);

// after: use the Builder, which builds the factory from properties
AMQPObservableQueue q = new AMQPObservableQueue.Builder(properties).build(useExchange, queueURI, queueType);

// Validate before constructing directly
if (factory == null) {
    throw new IllegalArgumentException("factory required; use AMQPObservableQueue.Builder");
}

When it happens

Trigger: Calling `new AMQPObservableQueue(null, addresses, ...)` directly instead of through AMQPObservableQueue.Builder, which guarantees a non-null factory.

Common situations: Unit-test wiring that passes null for the factory; a custom queue factory that bypasses the Builder.

Related errors

• Addresses are undefined
• Settings are undefined
• Batch size must be greater than 0
• Poll time must be greater than 0 ms
• Hosts are undefined

AI-assisted analysis of conductor-oss/conductor@cf7c3e4a8a (2026-08-14). Data as JSON: /api/errors/69c15bdb0bff49d0. Report an issue: GitHub.