quarkusio/quarkus · error · MessageBundleException

%s is not an enum constant of %s: %s

Error message

%s is not an enum constant of %s: %s

What it means

Qute supports per-enum-constant messages with keys of the form EnumName_CONSTANT or _$ prefix conventions. When isEnumConstantMessageKey resolves a key to an enum type, it verifies the constant actually exists as an enum constant field on that enum; if not, the build fails reporting the constant, the enum, and the key. This guards against typos in enum-constant message keys.

Source

Thrown at extensions/qute/deployment/src/main/java/io/quarkus/qute/deployment/MessageBundleProcessor.java:946

    private boolean isEnumConstantMessageKey(String separator, String key, IndexView index, ClassInfo bundleInterface) {
        int lastIdx = key.lastIndexOf(separator);
        if (lastIdx != -1 && lastIdx != key.length()) {
            String methodName = key.substring(0, lastIdx);
            String constant = key.substring(lastIdx + separator.length(), key.length());
            MethodInfo method = messageBundleMethod(bundleInterface, methodName);
            if (method != null && method.parametersCount() == 1) {
                Type paramType = method.parameterType(0);
                if (paramType.kind() == org.jboss.jandex.Type.Kind.CLASS) {
                    ClassInfo maybeEnum = index.getClassByName(paramType.name());
                    if (maybeEnum != null && maybeEnum.isEnum()) {
                        if (maybeEnum.fields().stream()
                                .filter(FieldInfo::isEnumConstant)
                                .map(FieldInfo::name)
                                .anyMatch(constant::equals)) {
                            return true;
                        }
                        throw new MessageBundleException(
                                String.format("%s is not an enum constant of %s: %s", constant, maybeEnum, key));
                    }
                }
            }
        }
        return false;
    }

    private void constructLine(StringBuilder builder, Iterator<String> it) {
        if (it.hasNext()) {
            String nextLine = adaptLine(it.next());
            if (nextLine.endsWith("\\")) {
                builder.append(nextLine.substring(0, nextLine.length() - 1));
                constructLine(builder, it);
            } else {
                builder.append(nextLine);
            }
        }

View on GitHub (pinned to e1c734241f)

Solutions

1. Fix the key in the properties file to use an existing enum constant, e.g. `Color_GREEN` instead of `Color_RED`.
2. Or re-add the missing constant to the enum if it should exist.
3. Regenerate/verify the list of constants against the enum source before re-building.

Example fix

// before (messages.properties)
Color_RED=Red color
// enum Color { GREEN, BLUE }

// after
Color_GREEN=Green color

// Verify enum-constant keys reference real constants
EnumMap-check: for key "Color_RED", assert
java.util.Arrays.stream(Color.values()).anyMatch(e -> e.name().equals("RED"));

When it happens

Trigger: A properties key like `Color_RED` where Color enum has no RED constant (e.g. it is named `REDISH` or was renamed); key references a constant removed from the enum.

Common situations: Renaming or deleting enum constants without updating per-constant message keys in bundle properties files; misspelling the constant part of the key; copying keys between projects with slightly different enums.

Related errors

• Message bundle name [%s] declared on %s must be a valid name
• Message bundle interface name conflict - [%s] is used for bo
• Locale of [%s] conflicts with the locale [%s] of the default
• Cannot register [%s] - a localized message bundle interface
• @MessageBundle must be declared on an interface: {bundleClas

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/74a5451a60616bd1. Report an issue: GitHub.