What causes "Invalid regex pattern in `table_name`: , resolved pattern: " in apache/seatunnel?

Fix the `table_name` regex: balance brackets/parens and quote literal dots as `\\.` in HOCON

apache/seatunnel · error · IllegalArgumentException

Invalid regex pattern in `table_name`: , resolved pattern:

Error message

Invalid regex pattern in `table_name`: , resolved pattern:

What it means

compilePattern wraps Java's Pattern.compile for the database and table regex fragments derived from `table_name`. If the resolved fragment is not a valid Java regex, the PatternSyntaxException is rethrown as an IllegalArgumentException that includes both the raw `table_name` value and the resolved sub-pattern, so the user can see which part failed. This catches malformed regex like unbalanced brackets or bad quantifiers.

Source

Thrown at seatunnel-connectors-v2/connector-hive/src/main/java/org/apache/seatunnel/connectors/seatunnel/hive/source/config/HiveSourceTableDiscovery.java:91

                }
                List<String> tables = catalog.listTables(databaseName);
                for (String tableName : tables) {
                    if (tablePattern.matcher(tableName).matches()) {
                        tablePaths.add(TablePath.of(databaseName, tableName));
                    }
                }
            }
        }

        tablePaths.sort(Comparator.comparing(TablePath::getFullName));
        return tablePaths;
    }

    private static Pattern compilePattern(String pattern, String rawTableName) {
        try {
            return Pattern.compile(pattern);
        } catch (PatternSyntaxException exception) {
            throw new IllegalArgumentException(
                    "Invalid regex pattern in `table_name`: "
                            + rawTableName
                            + ", resolved pattern: "
                            + pattern,
                    exception);
        }
    }

    /**
     * Treat databasePattern as an exact database name only when it doesn't contain obvious regex
     * meta characters.
     */
    private static boolean isExactDatabaseName(String databasePattern) {
        if (databasePattern == null || databasePattern.isEmpty()) {
            return false;
        }
        for (int i = 0; i < databasePattern.length(); i++) {
            char ch = databasePattern.charAt(i);

View on GitHub (pinned to cf67b549a7)

Solutions

Fix the `table_name` regex: balance brackets/parens and quote literal dots as `\\.` in HOCON
Test the pattern in plain Java regex before putting it in the config
Use the documented examples like `db0.\\.*` or `db1.user_table_[0-9]+` as templates

Example fix

// before
table_name = "db1.[app|web]order_\\.*" // '[' opens a char class but alternation '|' inside [ ] is literal, often unintended

// after
table_name = "db1.(app|web)order_\\.*"

Defensive patterns

Strategy: validation

Validate before calling

try {
    java.util.regex.Pattern.compile(tableNamePattern);
} catch (java.util.regex.PatternSyntaxException e) {
    throw new IllegalArgumentException("Invalid table_name regex: " + tableNamePattern, e);
}

Try / catch

try {
    // submit job / call discovery
} catch (IllegalArgumentException e) {
    if (e.getMessage() != null && e.getMessage().contains("Invalid regex pattern")) {
        // fix table_name regex and resubmit
    }
}

Prevention

Test regex in plain Java before putting it in HOCON
Escape literal dots as \\. (\\\\. in HOCON strings)
Balance all character classes and groups

When it happens

Trigger: discoverTablePaths with use_regex=true calls compilePattern on the parsed databasePattern or tablePattern fragment and Pattern.compile throws PatternSyntaxException (e.g. `table_name = "db[.orders"` with an unclosed `[`).

Common situations: Users hand-write regex with unescaped dots or unbalanced character classes; HOCON escaping confusion (single vs double backslash) corrupts `\.` into a bare dot that then forms invalid regex; copy-pasted globs (`*`) used as regex.

Related errors

AI-assisted analysis of apache/seatunnel@cf67b549a7 (2026-09-10). Data as JSON: /api/errors/5fa71ae04a2185c3. Report an issue: GitHub.