? UUID in Java

? Quick Overview

UUID (Universally Unique Identifier) is a 128-bit value used to uniquely identify information across systems. In Advanced Java, UUIDs are commonly used for database primary keys, distributed systems, session identifiers, and API tokens.

? Key Concepts

• UUID is defined in java.util.UUID
• Guarantees very high uniqueness
• Does not depend on a central authority
• Safe for distributed and concurrent systems

? Syntax / Theory

A UUID is represented as a 36-character string (32 hex digits + 4 hyphens). Java provides built-in methods to generate and parse UUID values.

? Code Example(s)

// Generating a random UUID using Java
import java.util.UUID;

public class UUIDExample {
public static void main(String[] args) {
UUID uuid = UUID.randomUUID();
System.out.println(uuid);
}
}

// Converting UUID to String and back to UUID
import java.util.UUID;

public class UUIDConversion {
public static void main(String[] args) {
UUID original = UUID.randomUUID();
String uuidStr = original.toString();
UUID parsed = UUID.fromString(uuidStr);
System.out.println(parsed);
}
}

? Live Output / Explanation