t8y2/dbx · error · SQLException

JDBC driver rejected connect for URL '" + url + "'

Error message

JDBC driver rejected connect for URL '" + url + "'

What it means

The plugin first tries the explicitly registered driver's Driver.connect(url, properties). If that call fails with UnsupportedOperationException or AbstractMethodError — meaning the driver class is present but its connect() is not really implemented for this URL/protocol — the plugin wraps it in a SQLException with this message. This catches drivers that were registered but do not actually accept the given URL scheme.

Source

Thrown at plugins/jdbc/src/main/java/app/dbx/jdbc/DbxJdbcPlugin.java:678

        }
        // Prefer the explicitly registered driver. DriverManager.getConnection only catches
        // SQLException; Hive/Inceptor drivers may throw UnsupportedOperationException for optional
        // methods, which aborts connect before the intended driver is reached.
        sharedConnection = connectWithRegisteredDriver(url, properties);
        sharedConnectionKey = key;
        configureOrdinaryAutoCommit(sharedConnection);
        return sharedConnection;
    }

    private static Connection connectWithRegisteredDriver(String url, Properties properties) throws SQLException {
        if (registeredDriver != null) {
            try {
                Connection connection = registeredDriver.connect(url, properties);
                if (connection != null) {
                    return connection;
                }
            } catch (UnsupportedOperationException | AbstractMethodError error) {
                throw new SQLException("JDBC driver rejected connect for URL '" + url + "'", error);
            }
        }
        try {
            return DriverManager.getConnection(url, properties);
        } catch (UnsupportedOperationException | AbstractMethodError error) {
            throw new SQLException("JDBC DriverManager rejected connect for URL '" + url + "'", error);
        }
    }

    private static String describeThrowable(Throwable error) {
        if (error == null) {
            return "unknown error";
        }
        String message = error.getMessage();
        if (message != null && !message.isBlank()
            && !message.equals(error.getClass().getName())
            && !message.equals(error.getClass().getSimpleName())) {
            return error.getClass().getName() + ": " + message.trim();

View on GitHub (pinned to c0390bff16)

Solutions

  1. Check that the JDBC URL scheme matches the registered driver (e.g. jdbc:postgresql:... with org.postgresql.Driver).
  2. Register/depend on the official, current driver JAR for the target database instead of a repackaged or partial jar.
  3. Update the driver to a recent release; AbstractMethodError indicates binary incompatibility between driver and JDK/JDBC API version.
  4. Note the plugin falls back to DriverManager.getConnection afterwards — check the follow-up error; if this one persists alone, the registered shim itself is broken, so fix driver discovery/registration.

Example fix

// before
url = "jdbc:mysql://host:3306/db";      // but org.postgresql.Driver registered
// after
url = "jdbc:postgresql://host:5432/db"; // matches registered driver
Defensive patterns

Strategy: try-catch

Validate before calling

// Java: confirm driver accepts the URL scheme before connecting
static boolean driverAccepts(java.sql.Driver d, String url) throws SQLException {
    try { return d.acceptsURL(url); } catch (Exception e) { return false; }
}

Try / catch

try {
    connection = plugin.open(connCfg);
} catch (java.sql.SQLException e) {
    if (e.getMessage() != null && e.getMessage().startsWith("JDBC driver rejected connect")) {
        throw new IllegalStateException("URL scheme does not match registered driver: " + e.getMessage(), e);
    }
    throw e;
}

Prevention

When it happens

Trigger: Calling openConnection (via handle/conn/genericTableObjectSource) where registeredDriver.connect() throws UnsupportedOperationException or AbstractMethodError — typically a stub driver, a driver whose class was force-registered from a JAR scan but whose URL scheme (jdbc:xyz:) doesn't match, or an ancient/partial driver implementation.

Common situations: Registering a generic JAR whose discovered class isn't the real Driver, mixing driver versions (old driver jar that lacks connect logic for new URL formats), or dialect mismatch like using a MySQL URL against a registered PostgreSQL driver shim.

Related errors

AI-assisted analysis of t8y2/dbx@c0390bff16 (2026-09-05). Data as JSON: /api/errors/16a5231a3620a663. Report an issue: GitHub.