gradle/gradle · error · IllegalStateException

Can not use getCredentials() method when not using PasswordC

Error message

Can not use getCredentials() method when not using PasswordCredentials; please use getCredentials(Class)

What it means

The parameterless getCredentials() on Maven/Ivy repositories is a convenience hard-wired to PasswordCredentials: on first call it installs PasswordCredentials, otherwise it returns them. If the repository already uses a different credentials type (e.g. AwsCredentials configured earlier), the instanceof check fails and IllegalStateException directs you to the typed variant getCredentials(Class).

Source

Thrown at platforms/software/dependency-management/src/main/java/org/gradle/api/internal/artifacts/repositories/AuthenticationSupporter.java:62

    private final ProviderFactory providerFactory;

    private final Property<Credentials> credentials;
    private boolean usesCredentials = false;

    public AuthenticationSupporter(Instantiator instantiator, ObjectFactory objectFactory, AuthenticationContainer authenticationContainer, ProviderFactory providerFactory) {
        this.instantiator = instantiator;
        this.authenticationContainer = authenticationContainer;
        this.credentials = objectFactory.property(Credentials.class);
        this.providerFactory = providerFactory;
    }

    public PasswordCredentials getCredentials() {
        if (!usesCredentials()) {
            return setCredentials(PasswordCredentials.class);
        } else if (credentials.get() instanceof PasswordCredentials) {
            return Cast.uncheckedCast(credentials.get());
        } else {
            throw new IllegalStateException("Can not use getCredentials() method when not using PasswordCredentials; please use getCredentials(Class)");
        }
    }

    public <T extends Credentials> T getCredentials(Class<T> credentialsType) {
        if (!usesCredentials()) {
            return setCredentials(credentialsType);
        } else if (credentialsType.isInstance(credentials.get())) {
            return Cast.uncheckedCast(credentials.get());
        } else {
            throw new IllegalArgumentException(String.format("Given credentials type '%s' does not match actual type '%s'", credentialsType.getName(), getCredentialsPublicType(credentials.get().getClass()).getName()));
        }
    }

    public void credentials(Action<? super PasswordCredentials> action) {
        if (usesCredentials() && !(credentials.get() instanceof PasswordCredentials)) {
            throw new IllegalStateException("Can not use credentials(Action) method when not using PasswordCredentials; please use credentials(Class, Action)");
        }
        credentials(PasswordCredentials.class, action);

View on GitHub (pinned to 534f27719b)

Solutions

1. Use the typed getter matching the configured type: repo.getCredentials(AwsCredentials.class).
2. In generic code, inspect the current credentials via repo.getCredentials(Credentials.class) — the base type always matches — and branch with instanceof.
3. If only username/password are needed everywhere, standardize repositories on PasswordCredentials.

Example fix

// before
repo.credentials(AwsCredentials.class) { accessKey = 'key'; secretKey = 'secret' }
def user = repo.credentials.username // implicit getCredentials() -> IllegalStateException
// after
def aws = repo.getCredentials(AwsCredentials.class)
println aws.accessKey

static boolean usesPasswordCredentials(MavenArtifactRepository repo) {
    return repo.getCredentials(Credentials.class) instanceof PasswordCredentials
}

When it happens

Trigger: repo.credentials(AwsCredentials.class) { ... } (or repo.getCredentials(AwsCredentials.class)) followed by repo.getCredentials() — for example generic code that introspects repository credentials on an S3 repository.

Common situations: Generic repository-auditing plugins calling the no-arg getter on every repository; builds mixing AWS and password credentials; migrations from password-only setups where the no-arg getter used to work.

Related errors

• Can not use credentials(Action) method when not using Passwo
• Given credentials type '%s' does not match actual type '%s'
• Unknown credentials type: '%s' (supported types: %s, %s and
• Credentials must be an instance of '%s'.
• Cannot fetch a model of type '%s' as this type is not an int

AI-assisted analysis of gradle/gradle@534f27719b (2026-08-22). Data as JSON: /api/errors/083a6d7c29caea2e. Report an issue: GitHub.