quarkusio/quarkus · error · IllegalStateException

Unknown plugin type!

Error message

Unknown plugin type!

What it means

PluginCommandFactory.createPluginCommand hits this IllegalStateException when a Quarkus CLI plugin descriptor has a PluginType that the factory's switch does not handle (the default branch). It indicates the plugin metadata declares a type outside the known set (e.g. jar/jbang vs. other supported kinds).

Source

Thrown at devtools/cli/src/main/java/io/quarkus/cli/plugin/PluginCommandFactory.java:50

    private Optional<PluginCommand> createPluginCommand(Plugin plugin) {
        switch (plugin.getType()) {
            case maven:
                return plugin.getLocation().flatMap(PluginUtil::checkGACTV).map(g -> new JBangCommand(toGAVC(g), output));
            case java:
            case jar:
            case jbang:
                return plugin.getLocation().map(l -> new JBangCommand(l, output));
            case executable:
                return plugin.getLocation().map(l -> new ShellCommand(plugin.getName(), Paths.get(l), output));
            case extension:
                if (PluginUtil.checkGACTV(plugin.getLocation()).isPresent()) {
                    return plugin.getLocation().flatMap(PluginUtil::checkGACTV).map(g -> new JBangCommand(toGAVC(g), output));
                } else if (plugin.getLocation().filter(l -> l.endsWith(".jar")).isPresent()) {
                    return plugin.getLocation().map(l -> new JBangCommand(l, output));
                }
            default:
                throw new IllegalStateException("Unknown plugin type!");
        }
    }

    /**
     * Create a command for the specified plugin
     */
    public Optional<CommandSpec> createCommand(Plugin plugin) {
        return createPluginCommand(plugin).map(createCommandSpec(plugin.getDescription().orElse("")));
    }

    public Function<PluginCommand, CommandSpec> createCommandSpec(String description) {
        return command -> {
            CommandSpec spec = CommandSpec.wrapWithoutInspection(command);
            if (!StringUtil.isNullOrEmpty(description)) {
                spec.usageMessage().description(description);
            }
            spec.parser().unmatchedArgumentsAllowed(true);
            spec.parser().unmatchedOptionsArePositionalParams(true);

View on GitHub (pinned to e1c734241f)

Solutions

1. Check the plugin descriptor YAML in ~/.quarkus/cli/plugins and set `type:` to a supported value (e.g. jar or jbang).
2. Remove the broken plugin entry (`quarkus plugin remove <name>` or delete its YAML) and reinstall it.
3. Upgrade the Quarkus CLI to match the version that wrote the plugin descriptor.

Example fix

# before (~/.quarkus/cli/plugins/foo.yaml)
type: maven
# after
type: jar

// inspect descriptor before install
type: $(yq '.type' ~/.quarkus/cli/plugins/<name>.yaml)
if [ "$type" != "jar" ] && [ "$type" != "jbang" ]; then
  echo "Unsupported plugin type: $type"; exit 1;
fi

public static boolean isKnownPluginType(Plugin p) {
    return p.getType() == PluginType.JAR || p.getType() == PluginType.JBANG;
}

try {
    Command cmd = factory.createPluginCommand(plugin, output);
} catch (IllegalStateException e) {
    if (e.getMessage().contains("Unknown plugin type")) {
        log.error("Plugin %s has an unsupported type; reinstall or upgrade the CLI".formatted(plugin.getName()));
    } else throw e;
}

When it happens

Trigger: Installing or invoking a CLI plugin whose descriptor (plugin YAML in ~/.quarkus/cli/plugins) specifies a plugin type the current CLI version cannot dispatch, so the switch falls through to `default: throw new IllegalStateException("Unknown plugin type!")`.

Common situations: A plugin created by a newer Quarkus CLI version introducing a new type; a hand-edited or corrupted plugin YAML with a mistyped `type:` field; leftover plugin descriptors after an upgrade/downgrade.

Related errors

• More than one @QuarkusMain method found with name '${name}':
• Build metrics file cannot be read:
• Build report file cannot be written to:
• The specified %s identifier (%s) contains invalid characters
• Algorithm not supported:

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/22cbe2ef7f165125. Report an issue: GitHub.