apache/flink · error · java.lang.IllegalArgumentException

Arrays must specify an 'items' property in node: {}

Error message

Arrays must specify an 'items' property in node: {}

What it means

Error "Arrays must specify an 'items' property in node: {}" thrown in apache/flink.

Source

Thrown at flink-formats/flink-json/src/main/java/org/apache/flink/formats/json/JsonRowSchemaConverter.java:282

            i++;
        }

        // validate that object does not contain additional properties
        if (node.has(ADDITIONAL_PROPERTIES)
                && node.get(ADDITIONAL_PROPERTIES).isBoolean()
                && node.get(ADDITIONAL_PROPERTIES).asBoolean()) {
            throw new IllegalArgumentException(
                    "An object must not allow additional properties in node: " + location);
        }

        return Types.ROW_NAMED(names, types);
    }

    private static TypeInformation<?> convertArray(String location, JsonNode node, JsonNode root) {
        // validate items
        if (!node.has(ITEMS)) {
            throw new IllegalArgumentException(
                    "Arrays must specify an '" + ITEMS + "' property in node: " + location);
        }
        final JsonNode items = node.get(ITEMS);

        // list (translated to object array)
        if (items.isObject()) {
            final TypeInformation<?> elementType = convertType(location + '/' + ITEMS, items, root);
            // result type might either be ObjectArrayTypeInfo or BasicArrayTypeInfo for Strings
            return Types.OBJECT_ARRAY(elementType);
        }
        // tuple (translated to row)
        else if (items.isArray()) {
            final TypeInformation<?>[] types = convertTypes(location + '/' + ITEMS, items, root);

            // validate that array does not contain additional items
            if (node.has(ADDITIONAL_ITEMS)
                    && node.get(ADDITIONAL_ITEMS).isBoolean()
                    && node.get(ADDITIONAL_ITEMS).asBoolean()) {

View on GitHub (pinned to 2f3c205e92)

Solutions

1. Address the cause reported by the error message: Arrays must specify an 'items' property in node: the reported value
2. Verify the inputs, configuration values, and classpath/dependency setup related to this operation, then retry.

Example fix

Correct the condition described ("Arrays must specify an 'items' property in node: the reported value") and rerun the job or command.

When it happens

Trigger: Triggered at runtime when the operation fails because: Arrays must specify an 'items' property in node: the reported value.

Common situations: Commonly caused by misconfiguration, missing dependencies or files, unsupported types or operations, or invalid user input leading to: Arrays must specify an 'items' property in node: the reported value.

AI-assisted analysis of apache/flink@2f3c205e92 (2026-08-14). Data as JSON: /api/errors/5411701c7697677f. Report an issue: GitHub.