public class USN
extends Object

Utility class for SSDP USN (Unique Service Name) header values and parsing.

This class provides constants and utility methods for handling USN header used in SSDP messages. The USN header provides a unique identifier for devices and services in UPnP networks.

Key features:

• Root device USN validation
• UDN (Unique Device Name) extraction
• USN parsing and manipulation
• UTF-8 encoding support
• Null-safe value handling

This class is used by SSDP components to parse and validate USN headers in discovery and advertisement messages, enabling proper device identification and service differentiation in UPnP networks.