redis/jedis · error · IllegalArgumentException

Aggregators must not contain null elements

Error message

Aggregators must not contain null elements

What it means

TSMRangeParams.aggregation(AggregationType[], long) also rejects arrays containing null elements with IllegalArgumentException("Aggregators must not contain null elements"). A null entry would produce an invalid AGGREGATION clause on the wire, so it is refused at parameter-construction time.

Solutions

1. Build the array with exact size, e.g. via list.toArray(new AggregationType[0]), rather than a pre-sized array with unfilled slots.
2. Filter nulls before calling: Arrays.stream(arr).filter(Objects::nonNull).toArray(AggregationType[]::new).
3. Fix the config/parser so unknown aggregator names are rejected or mapped to valid AggregationType values, not null.

Example fix

// before
AggregationType[] aggs = new AggregationType[3];
aggs[0] = AggregationType.AVG;
params.aggregation(aggs, 60000); // nulls -> throws
// after
List<AggregationType> aggs = new ArrayList<>();
aggs.add(AggregationType.AVG);
params.aggregation(aggs.toArray(new AggregationType[0]), 60000);

AggregationType[] cleaned = Arrays.stream(aggs).filter(Objects::nonNull).toArray(AggregationType[]::new);
if (cleaned.length == 0) throw new IllegalArgumentException("No valid aggregators");
params.aggregation(cleaned, bucketDuration);

boolean allNonNull(AggregationType[] a) {
  return Arrays.stream(a).allMatch(Objects::nonNull);
}

try {
  params.aggregation(aggs, bucketMs);
} catch (IllegalArgumentException e) {
  log.error("Null aggregator in array, check config mapping: {}", e.getMessage());
  throw e;
}

When it happens

Trigger: Passing an array such as {AggregationType.AVG, null}, typically produced by pre-sized arrays (new AggregationType[n]) that were only partially filled, or lists converted with nulls coming from config/parsers.

Common situations: Allocating new AggregationType[size] and populating fewer than size entries; deserializing aggregator lists from JSON/YAML where unknown values map to null; optional aggregation slots left unset in the array.

Related errors

• Aggregators must not contain null elements
• Aggregators must not contain null elements
• DriverInfo must not be null
• Aggregators must be non-null and non-empty
• FILTER arguments must be set.

AI-assisted analysis of redis/jedis@6dac31d4c2 (2026-09-08). Data as JSON: /api/errors/b8caf8d2d08203a9. Report an issue: GitHub.

Appendix: source

Thrown at src/main/java/redis/clients/jedis/timeseries/TSMRangeParams.java:162

  /**
   * Specifies multiple aggregators to be applied in a single {@code TS.MRANGE} / {@code TS.MREVRANGE} call. Aggregators are
   * sent on the wire in the given order and the response values appear in the same order in {@link TSElement#getValues()}.
   * Single-element arrays are accepted and behave like {@link #aggregation(AggregationType, long)}.
   *
   * @param aggregators ordered, non-empty list of aggregators
   * @param bucketDuration aggregation bucket duration in milliseconds
   * @return this
   * @throws IllegalArgumentException if {@code aggregators} is empty
   */
  public TSMRangeParams aggregation(AggregationType[] aggregators, long bucketDuration) {
    if (aggregators != null) {
      if (aggregators.length == 0) {
        throw new IllegalArgumentException("Aggregators must be non-null and non-empty");
      }
      for (AggregationType a : aggregators) {
        if (a == null) {
          throw new IllegalArgumentException("Aggregators must not contain null elements");
        }
      }
      this.aggregators = aggregators;
      this.bucketDuration = bucketDuration;
    } else {
      this.aggregators = null;
      this.bucketDuration = 0;
    }
    return this;
  }

  /**
   * This requires AGGREGATION.
   */
  public TSMRangeParams bucketTimestamp(String bucketTimestamp) {
    this.bucketTimestamp = encode(bucketTimestamp);
    return this;
  }

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