apache/maven · error · UnsupportedProtocolException

Cannot find wagon which supports the requested protocol: " +

Error message

Cannot find wagon which supports the requested protocol: " + protocol

What it means

Error "Cannot find wagon which supports the requested protocol: " + protocol" thrown in apache/maven.

Source

Thrown at compat/maven-compat/src/main/java/org/apache/maven/repository/legacy/DefaultWagonManager.java:701

    @Deprecated
    public Wagon getWagon(Repository repository) throws UnsupportedProtocolException {
        return getWagon(repository.getProtocol());
    }

    @Override
    @Deprecated
    public Wagon getWagon(String protocol) throws UnsupportedProtocolException {
        if (protocol == null) {
            throw new UnsupportedProtocolException("Unspecified protocol");
        }

        String hint = protocol.toLowerCase(java.util.Locale.ENGLISH);

        Wagon wagon;
        try {
            wagon = container.lookup(Wagon.class, hint);
        } catch (ComponentLookupException e) {
            throw new UnsupportedProtocolException(
                    "Cannot find wagon which supports the requested protocol: " + protocol, e);
        }

        return wagon;
    }
}

View on GitHub (pinned to e4093d4e12)

When it happens

Trigger: Thrown at compat/maven-compat/src/main/java/org/apache/maven/repository/legacy/DefaultWagonManager.java:701 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/854135531afd6b61. Report an issue: GitHub.