quarkusio/quarkus · warning · MultipleExtensionsFoundException

Multiple extensions found for keyword (no message; handled a

Error message

Multiple extensions found for keyword (no message; handled and reported as "Multiple extensions matching '${keyword}'" with the extension list)

What it means

planInstallation throws MultipleExtensionsFoundException when a keyword matches more than one catalog extension and the keyword is not a wildcard pattern. It is handled upstream: the handler reports 'Multiple extensions matching <keyword>' with the candidate list instead of failing hard.

Source

Thrown at independent-projects/tools/devtools-common/src/main/java/io/quarkus/devtools/commands/handlers/AddExtensionsCommandHandler.java:154

                for (Extension e : invocation.getExtensionsCatalog().getExtensions()) {
                    if (e.getArtifact().getKey().equals(artifactKey)) {
                        listed = List.of(e);
                        break;
                    }
                }

                //builder.addManagedExtension(new ArtifactCoords(artifactKey, null));
            } else {
                listed = listInternalExtensions(quarkusCore, keyword, catalog.getExtensions());
            }
            if (listed.isEmpty()) {
                // No extension found for this keyword.
                builder.addUnmatchedKeyword(keyword);
            }
            // If it's a pattern allow multiple results
            // See https://github.com/quarkusio/quarkus/issues/11086#issuecomment-666360783
            else if (listed.size() > 1 && !ExtensionPredicate.isPattern(keyword)) {
                throw new MultipleExtensionsFoundException(keyword, listed);
            }
            for (Extension e : listed) {
                final ArtifactCoords extensionCoords = e.getArtifact();
                boolean managed = false;
                ExtensionOrigin firstPlatform = null;
                ExtensionOrigin preferredOrigin = null;
                for (ExtensionOrigin origin : e.getOrigins()) {
                    if (!origin.isPlatform()) {
                        continue;
                    }
                    if (importedPlatforms.contains(origin.getBom())) {
                        managed = true;
                        builder.addManagedExtension(extensionCoords);
                        break;
                    }
                    if (preferredOrigin == null) {
                        if (preferredBoms.contains(origin.getBom())) {
                            preferredOrigin = origin;

View on GitHub (pinned to e1c734241f)

Solutions

Use the exact extension name or full GAV (groupId:artifactId)
Use a wildcard pattern (e.g. quarkus-rest*) if multiple matches are intended
Run the list command to inspect matching extensions before adding
Update scripts to the new canonical names after upgrading Quarkus

Example fix

// before
invocation.extensions().add("rest");
// after
invocation.extensions().add("quarkus-rest-jackson");

Defensive patterns

Strategy: validation

Validate before calling

List<String> matches = catalog.getExtensions().stream()
    .map(Extension::getArtifact).map(ArtifactCoords::getArtifactId)
    .filter(id -> id.contains(keyword)).toList();
if (matches.size() > 1 && !keyword.contains("*")) throw new IllegalArgumentException("Ambiguous keyword '" + keyword + "': " + matches);

Type guard

static boolean isUnambiguous(String keyword, List<String> ids) {
    return ids.stream().filter(id -> id.contains(keyword)).count() <= 1 || ExtensionPredicate.isPattern(keyword);
}

Try / catch

try { plan = handler.planInstallation(invocation, keywords); } catch (MultipleExtensionsFoundException e) { System.out.println("Pick one of: " + e.getListedExtensions()); }

Prevention

Always use full artifact ids or GAVs in scripts
Check extension names after Quarkus upgrades (renames/splits)
Use wildcard patterns intentionally, not by accident
Preview matches with the list command before adding

When it happens

Trigger: Calling planInstallation (or extensionInstallPlan) with a keyword like 'rest' that matches several extensions (e.g. rest, rest-jackson, resteasy) and is not a '*' pattern.

Common situations: Typing a short or generic extension name in 'quarkus add extension'; scripts relying on partial names after a Quarkus version renamed/split extensions (e.g. resteasy-reactive -> quarkus-rest).

Related errors

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/7c61017f71a44cd1. Report an issue: GitHub.