prestodb/presto · error · IllegalArgumentException

Unparseable port number:

Error message

Unparseable port number: 

What it means

When fromString finds a port suffix it parses it as a plain decimal integer. A leading '+' is rejected explicitly (JDK7 Integer.parseInt accepts it, but URI authority syntax does not), and any value Integer.parseInt cannot parse raises this error. The message quotes the full hostPortString for diagnosis.

Source

Thrown at presto-spi/src/main/java/com/facebook/presto/spi/HostAddress.java:206

        else {
            int colonPos = hostPortString.indexOf(':');
            if (colonPos >= 0 && hostPortString.indexOf(':', colonPos + 1) == -1) {
                // Exactly 1 colon.  Split into host:port.
                host = hostPortString.substring(0, colonPos);
                portString = hostPortString.substring(colonPos + 1);
            }
            else {
                // 0 or 2+ colons.  Bare hostname or IPv6 literal.
                host = hostPortString;
            }
        }

        int port = NO_PORT;
        if (portString != null && portString.length() != 0) {
            // Try to parse the whole port string as a number.
            // JDK7 accepts leading plus signs. We don't want to.
            if (portString.startsWith("+")) {
                throw new IllegalArgumentException("Unparseable port number: " + hostPortString);
            }
            try {
                port = Integer.parseInt(portString);
            }
            catch (NumberFormatException e) {
                throw new IllegalArgumentException("Unparseable port number: " + hostPortString);
            }
            if (!isValidPort(port)) {
                throw new IllegalArgumentException("Port number out of range: " + hostPortString);
            }
        }

        return new HostAddress(host, port);
    }

    public static HostAddress fromUri(URI httpUri)
    {
        String host = httpUri.getHost();

View on GitHub (pinned to 55bb57d202)

Solutions

1. Remove any leading '+' from the port substring
2. Ensure the port suffix is pure ASCII digits 0-9
3. Validate the "host:port" string with a regex like ^[^:]+:(\d+)$ before parsing
4. Log the offending hostPortString to find the malformed source value

Example fix

// before
HostAddress.fromUri(new URI("http://host:+8080"));
// after
HostAddress.fromUri(new URI("http://host:8080"));

int idx = hostPort.lastIndexOf(':');
String portStr = hostPort.substring(idx + 1);
if (portStr.startsWith("+") || !portStr.matches("\\d+")) {
    throw new IllegalArgumentException("Port suffix must be plain digits: " + hostPort);
}

try {
    addr = HostAddress.fromString(hostPort);
} catch (IllegalArgumentException e) {
    throw new IllegalArgumentException("Bad host:port value in config: " + hostPort, e);
}

When it happens

Trigger: HostAddress.fromString("host:+8080") (leading plus) or fromString("host:80 80"), "host:8080x", "host:0x1F90", "host:8_080" — any port substring that is not pure decimal digits.

Common situations: Copy-pasted addresses with typographic or unicode digits; templated configs where the port variable was left empty or contained a placeholder; hand-built strings with stray characters.

Related errors

• Port is invalid:
• host contains a port declaration:
• Invalid bracketed host/port:
• Port number out of range:
• INVALID_FUNCTION_ARGUMENT

AI-assisted analysis of prestodb/presto@55bb57d202 (2026-09-04). Data as JSON: /api/errors/7a51cd66bb42a249. Report an issue: GitHub.