apache/flink · error · IllegalArgumentException

Row type information expected.

Error message

Row type information expected.

What it means

Error "Row type information expected." thrown in apache/flink.

Source

Thrown at flink-formats/flink-csv/src/main/java/org/apache/flink/formats/csv/RowCsvInputFormat.java:348

    /** A builder for creating a {@link RowCsvInputFormat}. */
    public static class Builder implements Serializable {

        private final Path[] filePaths;
        private final TypeInformation[] fieldTypes;
        private CsvSchema csvSchema;
        private boolean ignoreParseErrors;
        private int[] selectedFields;

        /**
         * Creates a row CSV input format for the given {@link TypeInformation} and file paths with
         * optional parameters.
         */
        private Builder(TypeInformation<Row> typeInfo, Path... filePaths) {
            checkNotNull(filePaths, "File paths must not be null.");
            checkNotNull(typeInfo, "Type information must not be null.");

            if (!(typeInfo instanceof RowTypeInfo)) {
                throw new IllegalArgumentException("Row type information expected.");
            }

            this.filePaths = filePaths;
            this.fieldTypes = ((RowTypeInfo) typeInfo).getFieldTypes();
            this.csvSchema = CsvRowSchemaConverter.convert((RowTypeInfo) typeInfo);
        }

        public Builder setFieldDelimiter(char delimiter) {
            this.csvSchema = this.csvSchema.rebuild().setColumnSeparator(delimiter).build();
            return this;
        }

        public Builder setAllowComments(boolean allowComments) {
            this.csvSchema = this.csvSchema.rebuild().setAllowComments(allowComments).build();
            return this;
        }

        public Builder setArrayElementDelimiter(String delimiter) {

View on GitHub (pinned to 2f3c205e92)

Solutions

1. Address the cause reported by the error message: Row type information expected.
2. Verify the inputs, configuration values, and classpath/dependency setup related to this operation, then retry.

Example fix

Correct the condition described ("Row type information expected.") and rerun the job or command.

When it happens

Trigger: Triggered at runtime when the operation fails because: Row type information expected.

Common situations: Commonly caused by misconfiguration, missing dependencies or files, unsupported types or operations, or invalid user input leading to: Row type information expected.

AI-assisted analysis of apache/flink@2f3c205e92 (2026-08-14). Data as JSON: /api/errors/dafc7d56174a0d49. Report an issue: GitHub.