apache/maven · error · IllegalStateException

No instance of ${clazz.getName()} is bound to the session sc

Error message

No instance of ${clazz.getName()} is bound to the session scope.

What it means

SessionScope.seededKeySupplier is the fallback supplier bound for session-scoped keys. When such a key is resolved and no real instance has been seeded or computed for the current session scope state, the supplier throws IllegalStateException("No instance of <class> is bound to the session scope.") — the session scope holds no binding for that type.

Source

Thrown at impl/maven-impl/src/main/java/org/apache/maven/impl/di/SessionScope.java:185

            return value;
        }

        @Override
        public T get() {
            if (value == null) {
                synchronized (this) {
                    if (value == null) {
                        value = provider.get();
                    }
                }
            }
            return value;
        }
    }

    public static <T> Supplier<T> seededKeySupplier(Class<? extends T> clazz) {
        return () -> {
            throw new IllegalStateException("No instance of " + clazz.getName() + " is bound to the session scope.");
        };
    }
}

View on GitHub (pinned to e4093d4e12)

Solutions

1. Seed the instance before resolution: sessionScope.enter(); sessionScope.seed(MyComponent.class, instance);
2. Bind the type normally (unscoped or session-scoped with a real provider) instead of relying on the seeded placeholder key
3. Resolve the dependency lazily inside the session lifecycle, after Maven has seeded it

Example fix

// before
sessionScope.enter();
MyComponent c = injector.getInstance(MyComponent.class); // IllegalStateException: not seeded

// after
sessionScope.enter();
sessionScope.seed(MyComponent.class, new MyComponentImpl());
MyComponent c = injector.getInstance(MyComponent.class);

// seed the session scope before resolving the key
sessionScope.enter();
try {
    sessionScope.seed(MyComponent.class, new MyComponentImpl());
    MyComponent c = injector.getInstance(MyComponent.class);
} finally {
    sessionScope.exit();
}

try {
    MyComponent c = injector.getInstance(MyComponent.class);
} catch (IllegalStateException e) {
    if (e.getMessage() != null && e.getMessage().contains("session scope")) {
        throw new IllegalStateException("MyComponent must be seeded into the session scope first", e);
    }
    throw e;
}

When it happens

Trigger: Resolving a session-scoped key before SessionScope.seed(...) provided the instance; bindings that reference the seeded key directly instead of going through the scope's scope() wrapper; resolving after exit() dropped the seeded values.

Common situations: Test setups binding a placeholder key but forgetting seed(); components depending on a session-scoped type that Maven never seeds in the current lifecycle phase; refactors renaming seeded classes so old keys remain bound to placeholders.

Related errors

• Cannot access session scope outside of a scoping block
• No instance of {} is bound to the mojo execution scope.
• Cannot access {} outside of a scoping block
• Error while initializing binding {}
• Cannot rebind scope annotation class to a different implemen

AI-assisted analysis of apache/maven@e4093d4e12 (2026-08-21). Data as JSON: /api/errors/e1fb2672fc00e946. Report an issue: GitHub.