quarkusio/quarkus · error · UnsupportedOperationException

Stateless operations not supported

Error message

Stateless operations not supported

What it means

ManagedBlockingOperations wraps a managed (persistence-context) blocking Hibernate Session. getStatelessSession(entityClass) would need to hand out a StatelessSession, which the managed delegate cannot provide (the source even marks it with a FIXME). Because managed operations objects never expose stateless sessions, the method throws UnsupportedOperationException.

Source

Thrown at extensions/data/hibernate/runtime/src/main/java/io/quarkus/data/hibernate/runtime/orm/ManagedBlockingOperations.java:32

import io.quarkus.data.hibernate.runtime.spi.PanacheBlockingOperations;

public class ManagedBlockingOperations implements PanacheBlockingOperations {

    public final static ManagedBlockingOperations INSTANCE = new ManagedBlockingOperations();
    private final static ManagedBlockingJpaOperations DELEGATE = new ManagedBlockingJpaOperations();

    private ManagedBlockingOperations() {
    }

    @Override
    public Session getSession(Class<?> entityClass) {
        return DELEGATE.getSession(entityClass);
    }

    @Override
    public StatelessSession getStatelessSession(Class<?> entityClass) {
        // FIXME: this is wrong
        throw new UnsupportedOperationException("Stateless operations not supported");
    }

    @Override
    public Void insert(Object entity) {
        throw new UnsupportedOperationException("Stateless operations not supported");
    }

    @Override
    public Void persist(Object entity) {
        DELEGATE.persist(entity);
        return null;
    }

    @Override
    public Void persistAndFlush(Object entity) {
        DELEGATE.persist(entity);
        DELEGATE.flush(entity);
        return null;

View on GitHub (pinned to e1c734241f)

Solutions

  1. Obtain the StatelessSession directly from the session factory (openStatelessSession) instead of via the managed wrapper
  2. Use the dedicated stateless operations object for stateless work (insert/upsert/delete)
  3. Restructure code so managed and stateless operations use separate, explicitly obtained handles
  4. Track upstream Quarkus updates in case the FIXME is resolved and stateless support is added

Example fix

// before
StatelessSession sss = managedOps.getStatelessSession(User.class);
// after
StatelessSession sss = sessionFactory.openStatelessSession();
Defensive patterns

Strategy: try-catch

Validate before calling

// do not request a stateless session from a managed wrapper
// obtain it from the factory instead:
// StatelessSession sss = sessionFactory.openStatelessSession();

Try / catch

StatelessSession sss;
try {
    sss = managedOps.getStatelessSession(User.class);
} catch (UnsupportedOperationException e) {
    sss = sessionFactory.openStatelessSession();
}

Prevention

When it happens

Trigger: Calling getStatelessSession(SomeEntity.class) on a managed blocking operations/session wrapper, e.g. generic code that obtains either a managed or stateless view depending on context.

Common situations: Utility code abstracting over both managed and stateless access paths; developers trying to mix stateless batch operations into a managed session handle; version drift where the managed wrapper's API surface grew but stateless support was not implemented.

Related errors

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/6d91fd154d60bcd1. Report an issue: GitHub.