# ZoneId.of constructor

ZoneId.of(

1. String zoneId

)

Factory constructor to create a ZoneId from a string-based zone ID.

Validates that the input string is non-empty. Throws an InvalidArgumentException if an empty string is passed.

Example:

    ZoneId ny = ZoneId.of('America/New_York');

`zoneId` must be a valid time zone name, such as 'UTC' or 'Asia/Tokyo'. This class does not validate against all IANA time zones, but you can use ZoneId.getAvailableZoneIds for commonly supported names. Represents a time zone identifier, abstracting the concept of region-based or offset-based zone IDs (e.g., 'UTC', 'America/New_York').

The `ZoneId` class allows specifying or retrieving time zone information in a controlled and type-safe manner.

Example:

    ZoneId utc = ZoneId.of('UTC');
    print(utc.id); // Output: UTC

    ZoneId systemZone = ZoneId.systemDefault();
    print(systemZone); // Output: e.g., "PDT", "CET", depending on system

## Implementation

    factory ZoneId.of(String zoneId) {
      if (zoneId.isEmpty) {
        throw InvalidArgumentException('Zone ID cannot be empty');
      }
      return ZoneId._(zoneId);
    }