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Corda LeanState Maven Central

Shamelessly lazy or simply tired of manually maintaining ContractState / PersistentState mappings? LeanState (re)generates perfectly synced and consistent state classes at build-time, based on model interfaces like NewsPaper bellow as input:

interface NewsPaper {
   val publisher: Party?

You can (optionally!) extend Corda’s standard interfaces if you really need
custom overrides VS those added by the processor (e.g. for supportedSchemas()). The processor will refrain from generating its own if you do.
Such a requirement should be rare as generation is configurable in a few ways, see state model
and full example sections for details.

Here’s what NewsPaper above will generate with default settings (edited for brevity). Contract state:

@BelongsToContract(value = NewsPaperContract::class)
data class NewsPaperContractState(
        override val linearId: UniqueIdentifier = UniqueIdentifier(),
        override val publisher: Party? = null,
) : NewsPaperContract.NewsPaper, ParticipantsState, LinearState, QueryableState {
    override val participants: List<AbstractParty> = //...
    override fun generateMappedObject(schema: MappedSchema): NewsPaperPersistentState = //...
    override fun supportedSchemas(): Iterable<MappedSchema> = listOf(SchemaV1)
    object Schema
    object SchemaV1 : MappedSchema(, 1,

Persistent state (edited for brevity):

@Entity @Table(name = "news_paper")
class NewsPaperPersistentState(
  @Column(name = "linear_id_id",nullable = false) val linearIdId: UUID,
  @Column(name = "linear_id_external_id") val linearIdExternalId: String? = null,
  @Column(name = "publisher_name_common_name") val publisherNameCommonName: String? = null,
  @Column(name = "publisher_name_organisation_unit") val publisherNameOrganisationUnit: String? = null,
  @Column(name = "publisher_name_organisation") val publisherNameOrganisation: String?,
  @Column(name = "publisher_name_locality") val publisherNameLocality: String?,
  @Column(name = "publisher_name_state") val publisherNameState: String? = null,
  @Column(name = "publisher_name_country") val publisherNameCountry: String?,
) : PersistentState()