apache/seatunnel · error · IndexOutOfBoundsException

Index: , Fields size

Error message

Index: <index>, Fields size:<size>

What it means

Schema.get() is a custom accessor over an internal list of Field objects in the Doris REST table schema model. It throws IndexOutOfBoundsException when the requested index is >= the number of fields, deliberately including the size in the message since java.util.List.get's default message is less descriptive. It guards only the upper bound; a negative index will still be thrown by the underlying list.

Solutions

1. Check the index against schema.size() before calling get(index)
2. Re-fetch the Doris table schema if it may have changed (ALTER TABLE) instead of caching it
3. Fix loop bounds (use `<` not `<=`) when iterating fields

Example fix

// before
Field f = schema.get(index);
// after
if (index < 0 || index >= schema.size()) {
    throw new IllegalArgumentException("field index out of range: " + index);
}
Field f = schema.get(index);

if (schema == null || index < 0 || index >= schema.size()) return null;
Field f = schema.get(index);

boolean inRange(int i, Schema s) { return s != null && i >= 0 && i < s.size(); }

When it happens

Trigger: Calling Schema.get(i) with i >= schema.size() while walking the Doris FE /schema REST response, e.g. iterating with a stale or wrong field count, or parsing a schema whose fields were truncated by an FE misconfiguration.

Common situations: Parsing Doris table metadata during schema-based save-mode table creation; loop bounds mismatch after a concurrent ALTER TABLE changed the schema; off-by-one loops like `for (i = 0; i <= schema.size(); i++)`.

Related errors

• Can't find column in table.
• Close scanner from failed.
• CloseScanner result from
• Closing httpClient failed.
• Closing streamLoadHttpClient failed.

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/392999799a24abc5. Report an issue: GitHub.

Appendix: source

Thrown at seatunnel-connectors-v2/connector-doris/src/main/java/org/apache/seatunnel/connectors/doris/rest/models/Schema.java:77

    }

    public void put(
            String name,
            String type,
            String comment,
            int scale,
            int precision,
            String aggregationType) {
        properties.add(new Field(name, type, comment, scale, precision, aggregationType));
    }

    public void put(Field f) {
        properties.add(f);
    }

    public Field get(int index) {
        if (index >= properties.size()) {
            throw new IndexOutOfBoundsException(
                    "Index: " + index + ", Fields size:" + properties.size());
        }
        return properties.get(index);
    }

    public int size() {
        return properties.size();
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) {
            return true;
        }
        if (o == null || getClass() != o.getClass()) {
            return false;
        }
        Schema schema = (Schema) o;

View on GitHub (pinned to cf67b549a7)