quarkusio/quarkus · error · UnsupportedOperationException

Hints not supported yet

Error message

Hints not supported yet

What it means

withHint(String,Object) on the Hibernate Reactive Panache query impl accepts the hint into its map but then unconditionally throws UnsupportedOperationException("Hints not supported yet"). Query hints are simply not implemented for Hibernate Reactive Panache yet; the method exists for API parity with the blocking variant. Any call to it fails regardless of arguments.

Source

Thrown at extensions/panache/hibernate-reactive-panache-common/runtime/src/main/java/io/quarkus/hibernate/reactive/panache/common/runtime/CommonAbstractPanacheQueryImpl.java:240

            throw new UnsupportedOperationException("Cannot call a range related method, " +
                    "call range(int, int) to initiate range first");
        }
        if (page != null) {
            throw new UnsupportedOperationException("Cannot call a range related method in a paged query, " +
                    "call range(int, int) to initiate range first");
        }
    }

    public void withLock(LockModeType lockModeType) {
        this.lockModeType = lockModeType;
    }

    public void withHint(String hintName, Object value) {
        if (hints == null) {
            hints = new HashMap<>();
        }
        hints.put(hintName, value);
        throw new UnsupportedOperationException("Hints not supported yet");
    }

    // Results

    @SuppressWarnings("unchecked")
    public Uni<Long> count() {
        if (count == null) {
            // FIXME: question about caching the result here
            count = em.flatMap(session -> {
                if (customCountQueryForSpring != null) {
                    Mutiny.SelectionQuery<Long> countQuery = session.createSelectionQuery(customCountQueryForSpring,
                            Long.class);
                    if (paramsArrayOrMap instanceof Map)
                        AbstractJpaOperations.bindParameters(countQuery, (Map<String, Object>) paramsArrayOrMap);
                    else
                        AbstractJpaOperations.bindParameters(countQuery, (Object[]) paramsArrayOrMap);
                    return applyFilters(session, () -> countQuery.getSingleResult());
                } else {

View on GitHub (pinned to e1c734241f)

Solutions

  1. Remove the withHint(...) call; there is no reactive Panache support yet.
  2. Set equivalent configuration via Hibernate Reactive session/persistence-unit properties in application.properties (e.g. SQL/logging settings) rather than per-query hints.
  3. For fetch-size-like behavior, restructure the query (fetch joins, limits) instead of relying on hints.
  4. Track upstream Hibernate Reactive support for query hints before re-adding the call.

Example fix

// before
PanacheQuery<Person> q = Person.find("age > ?1", 18).withHint("org.hibernate.fetchSize", 50);

// after
PanacheQuery<Person> q = Person.find("age > ?1", 18); // hints not supported reactively
Defensive patterns

Strategy: validation

Validate before calling

// never call withHint on hibernate-reactive Panache queries
Objects.requireNonNull(hintName); // not sufficient — method always throws; remove the call

Try / catch

try { query.withHint(name, value); } catch (UnsupportedOperationException e) { log.warn("Hints unsupported on hibernate-reactive Panache; ignored"); }

Prevention

When it happens

Trigger: Any call to PanacheQuery.withHint(String hintName, Object value) on a Hibernate Reactive Panache query.

Common situations: Porting blocking Hibernate ORM Panache code (where withHint works) to hibernate-reactive-panache; adding cache/lock hints like org.hibernate.cacheable or org.hibernate.fetchSize copied from blocking code.

Related errors

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/ba76608ccf4ba4f7. Report an issue: GitHub.