apache/maven · error · UnsupportedInStandaloneModeException

This operation is not supported in standalone mode

Error message

This operation is not supported in standalone mode

What it means

Error "This operation is not supported in standalone mode" thrown in apache/maven.

Source

Thrown at impl/maven-impl/src/main/java/org/apache/maven/impl/standalone/ApiRunner.java:250

        @Override
        public Path getTopDirectory() {
            return null;
        }

        @Override
        public Path getRootDirectory() {
            throw new IllegalStateException();
        }

        @Override
        public List<Project> getProjects() {
            return List.of();
        }

        @Override
        public Map<String, Object> getPluginContext(Project project) {
            throw new UnsupportedInStandaloneModeException();
        }
    }

    @Provides
    @SuppressWarnings("unused")
    static Lookup newLookup(Injector injector) {
        return new Lookup() {
            @Override
            public <T> T lookup(Class<T> type) {
                try {
                    return injector.getInstance(type);
                } catch (DIException e) {
                    throw new MavenException("Unable to locate instance of type " + type, e);
                }
            }

            @Override
            public <T> T lookup(Class<T> type, String name) {

View on GitHub (pinned to e4093d4e12)

When it happens

Trigger: Thrown at impl/maven-impl/src/main/java/org/apache/maven/impl/standalone/ApiRunner.java:250 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of apache/maven@e4093d4e12 (2026-08-21). Data as JSON: /api/errors/81517a6144d4d071. Report an issue: GitHub.