redis/jedis · error · IllegalArgumentException

LIMIT must be non-negative

Error message

LIMIT must be non-negative

What it means

SUnionCardParams.limit() validates the cardinality cap client-side before the SUNIONCARD command is built. Jedis throws this IllegalArgumentException when a negative limit is passed, since Redis LIMIT only accepts non-negative values (0 means no cap).

Solutions

1. Clamp or validate the limit before calling limit(), e.g. Math.max(0, limit).
2. Omit the limit() call entirely when no cap is intended (LIMIT 0 is the default/no-limit).
3. Fix the upstream computation that produces a negative value.

Example fix

// before
SUnionCardParams params = new SUnionCardParams().limit(remaining - used);
// after
long limit = Math.max(0, remaining - used);
SUnionCardParams params = new SUnionCardParams().limit(limit);

if (limit < 0) throw new IllegalArgumentException("limit must be >= 0, got " + limit);
SUnionCardParams params = new SUnionCardParams().limit(limit);

boolean isValidLimit(long limit) { return limit >= 0; }

try {
  params = new SUnionCardParams().limit(limit);
} catch (IllegalArgumentException e) {
  params = new SUnionCardParams(); // fall back to no limit
}

When it happens

Trigger: Calling new SUnionCardParams().limit(n) with any n < 0, e.g. limit(-1) or a limit computed from an unvalidated subtraction that underflows.

Common situations: Computing a limit as difference of counters (remaining - used) that went negative; passing user-supplied pagination input without clamping; integer arithmetic bugs producing negative caps.

Related errors

• failed to connect. Please check configuration and try again.
• IDMP-DURATION must be between 1 and 86400 seconds
• IDMP-MAXSIZE must be between 1 and 10000
• client info cannot contain spaces, newlines or special…
• DriverInfo must not be null

AI-assisted analysis of redis/jedis@6dac31d4c2 (2026-09-08). Data as JSON: /api/errors/15e52a75c0616456. Report an issue: GitHub.

Appendix: source

Thrown at src/main/java/redis/clients/jedis/params/SUnionCardParams.java:46

  }

  /**
   * Return an approximate cardinality using HyperLogLog (standard error ~0.81%).
   * @return SUnionCardParams
   */
  public SUnionCardParams approx() {
    this.approx = true;
    return this;
  }

  /**
   * Cap the returned cardinality at {@code limit}. {@code LIMIT 0} means no limit.
   * @param limit non-negative cap
   * @return SUnionCardParams
   */
  public SUnionCardParams limit(long limit) {
    if (limit < 0) {
      throw new IllegalArgumentException("LIMIT must be non-negative");
    }
    this.limit = limit;
    return this;
  }

  @Override
  public void addParams(CommandArguments args) {
    if (approx) {
      args.add(Keyword.APPROX);
    }
    if (limit != null) {
      args.add(Keyword.LIMIT);
      args.add(limit);
    }
  }

  @Override
  public boolean equals(Object o) {

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