Module iu.util

Package edu.iu

Class IdGenerator

java.lang.Object

edu.iu.IdGenerator

public class IdGenerator
extends Object

Provides a utility for generating short cryptographically secure unique identifiers.

Identifiers generated by this utility are smaller and less likely to collide than the random (v4) UUID values from UUID.randomUUID().

• Generates 24 bytes of pseudorandom data, interposed with
  • The 4 byte seconds since epoch timestamp
  • The lower 3 bytes of a hash checksum seeded by the system timestamp
• Uses a modified Base64 transform to convert to an id-safe 32 character string
  • Includes only upper and lower case letters, digits, hyphen and underline characters
  • May be verified as having been generated by the same algorithm, optionally with a millisecond time to live

Method Summary

Modifier and Type	Method	Description
static String	generateId()	Generates a new unique identifier.
static void	verifyId(String id, long ttl)	Validates that a new unique identifier was created by the same algorithm used in this utility, and has not expired.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Details

generateId

public static String generateId()

Generates a new unique identifier.

Returns:

new unique identifier

verifyId

public static void verifyId(String id,
 long ttl)

Validates that a new unique identifier was created by the same algorithm used in this utility, and has not expired.

Parameters:

id - id to verify

ttl - millisecond time to live for determining the expiration time for the id; 0 for no expiration time