corda / net.corda.core.contracts / UniqueIdentifier

UniqueIdentifier

data class UniqueIdentifier : Comparable<UniqueIdentifier>

This class provides a truly unique identifier of a trade, state, or other business object, bound to any existing external ID. Equality and comparison are based on the unique ID only; if two states somehow have the same UUID but different external IDs, it would indicate a problem with handling of IDs.

Parameters

externalId - Any existing weak identifier such as trade reference ID. This should be set here the first time a UniqueIdentifier is created as part of state issuance, or ledger on-boarding activity. This ensure that the human readable identity is paired with the strong ID.

id - Should never be set by user code and left as default initialised. So that the first time a state is issued this should be given a new UUID. Subsequent copies and evolutions of a state should just copy the externalId and id fields unmodified.

Constructors

<init>

UniqueIdentifier(externalId: String? = null, id: UUID = UUID.randomUUID())

This class provides a truly unique identifier of a trade, state, or other business object, bound to any existing external ID. Equality and comparison are based on the unique ID only; if two states somehow have the same UUID but different external IDs, it would indicate a problem with handling of IDs.

Properties

externalId

val externalId: String?

Any existing weak identifier such as trade reference ID. This should be set here the first time a UniqueIdentifier is created as part of state issuance, or ledger on-boarding activity. This ensure that the human readable identity is paired with the strong ID.

id

val id: UUID

Should never be set by user code and left as default initialised. So that the first time a state is issued this should be given a new UUID. Subsequent copies and evolutions of a state should just copy the externalId and id fields unmodified.

Functions

compareTo

fun compareTo(other: UniqueIdentifier): Int

equals

fun equals(other: Any?): Boolean

hashCode

fun hashCode(): Int

toString

fun toString(): String

Companion Object Functions

fromString

fun fromString(name: String): UniqueIdentifier

Helper function for unit tests where the UUID needs to be manually initialised for consistency.

Extension Functions

contextLogger

fun Any.contextLogger(): Logger

When called from a companion object, returns the logger for the enclosing class.