Transaction
constructor(data: T, contract: ContractClassName = requireNotNull(data.requiredContractClassName) {
//TODO: add link to docsite page, when there is one.
"""
Unable to infer Contract class name because state class ${data::class.java.name} is not annotated with
@BelongsToContract, and does not have an enclosing class which implements Contract. Either annotate ${data::class.java.name}
with @BelongsToContract, or supply an explicit contract parameter to TransactionState().
""".trimIndent().replace('\n', ' ')
}, notary: Party, encumbrance: Int? = null, constraint: AttachmentConstraint = AutomaticPlaceholderConstraint)