apache/cassandra · error · IllegalStateException

Do not specify additional arguments when --category/-c is se

Error message

Do not specify additional arguments when --category/-c is set.

What it means

nodetool guardrails-config set/display rejects combining the --category/-c option with an additional positional guardrail-name argument, throwing IllegalStateException. The two ways of scoping output are exclusive: either a category or a specific guardrail.

Source

Thrown at src/java/org/apache/cassandra/tools/nodetool/GuardrailsConfigCommand.java:74

    @Command(name = "getguardrailsconfig", description = "Print runtime configuration of guardrails.")
    public static class GetGuardrailsConfig extends GuardrailsConfigCommand
    {
        @Option(names = { "--category", "-c" },
                description = "Category of guardrails to filter, can be one of 'values', 'thresholds', 'flags', 'others'.")
        private GuardrailCategory guardrailCategory;

        @Option(names = { "--expand" },
        description = "Expand all guardrail names so they reflect their counterparts in cassandra.yaml")
        private boolean expand = false;

        @Parameters(index = "0", arity = "0..1", description = "Specific name of a guardrail to get configuration of or all guardrails if not specified.")
        private String guardrailName;

        @Override
        public void execute(NodeProbe probe)
        {
            if (guardrailName != null && guardrailCategory != null)
                throw new IllegalStateException("Do not specify additional arguments when --category/-c is set.");

            Map<String, List<Method>> allGetters = parseGuardrailNames(probe.getGuardrailsMBean().getClass().getDeclaredMethods(), guardrailName);

            if (allGetters.isEmpty())
            {
                assert guardrailName != null;
                throw new IllegalStateException(format("Guardrail %s not found.", guardrailName));
            }

            display(probe, allGetters, guardrailCategory, expand);
        }

        @VisibleForTesting
        public static Map<String, List<Method>> parseGuardrailNames(Method[] guardrailsMethods, String guardrailName)
        {
            Map<String, List<Method>> allGetters = stream(guardrailsMethods)
                                                   .filter(method -> method.getName().startsWith("get")
                                                                     && !method.getName().endsWith("CSV")

View on GitHub (pinned to 88fd0f6a0e)

Solutions

  1. Remove the positional guardrail name and use only --category/-c.
  2. Remove --category/-c and query the single guardrail by name.
  3. Run `nodetool help guardrails-config` to see accepted argument shapes.

Example fix

// before
nodetool guardrailsconfig get --category read consistency
// after
nodetool guardrailsconfig get --category read
Defensive patterns

Strategy: validation

Validate before calling

def validate_guardrails_args(category, name):
    if category and name:
        raise SystemExit('Use either --category/-c or a guardrail name, not both.')

Try / catch

try {
    displayGuardrails(...);
} catch (IllegalStateException e) {
    System.err.println(e.getMessage() + " — drop either --category or the positional name.");
}

Prevention

When it happens

Trigger: Running e.g. `nodetool guardrailsconfig --category read myguardrail` — both a guardrail name argument and a category flag are supplied.

Common situations: Appending a guardrail name out of habit while a category flag is already present; scripting tools that add both filters unconditionally.

Related errors

AI-assisted analysis of apache/cassandra@88fd0f6a0e (2026-09-10). Data as JSON: /api/errors/b9186304253f8c61. Report an issue: GitHub.