elastic/elasticsearch · error · IllegalArgumentException

[field] must not be null: [{name}]

Error message

[field] must not be null: [{name}]

What it means

Error "[field] must not be null: [{name}]" thrown in elastic/elasticsearch.

Source

Thrown at modules/aggregations/src/main/java/org/elasticsearch/aggregations/metric/ArrayValuesSourceAggregationBuilder.java:130

        out.writeGenericValue(fields);
        out.writeOptionalWriteable(userValueTypeHint);
        out.writeOptionalString(format);
        out.writeGenericMap(missingMap);
        innerWriteTo(out);
    }

    /**
     * Write subclass' state to the stream
     */
    protected abstract void innerWriteTo(StreamOutput out) throws IOException;

    /**
     * Sets the field to use for this aggregation.
     */
    @SuppressWarnings("unchecked")
    public AB fields(List<String> fieldsArg) {
        if (fieldsArg == null) {
            throw new IllegalArgumentException("[field] must not be null: [" + name + "]");
        }
        this.fields = fieldsArg;
        return (AB) this;
    }

    /**
     * Gets the field to use for this aggregation.
     */
    public List<String> fields() {
        return fields;
    }

    /**
     * Sets the format to use for the output of the aggregation.
     */
    @SuppressWarnings("unchecked")
    public AB format(String formatArg) {
        if (formatArg == null) {

View on GitHub (pinned to db6a809a66)

When it happens

Trigger: Thrown at modules/aggregations/src/main/java/org/elasticsearch/aggregations/metric/ArrayValuesSourceAggregationBuilder.java:130 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of elastic/elasticsearch@db6a809a66 (2026-08-12). Data as JSON: /api/errors/f264caff303be36b. Report an issue: GitHub.