Amount class 中如何表示负数？

Question

根据文档，Amount class 中不允许使用负数：https://docs.corda.net/api/kotlin/corda/net.corda.core.contracts/-amount/

当 ContractState class 有一个可以为负数的 Amount 字段（例如可以多付的余额）时，表示负数的最佳方式是什么？

Answer 1

您不能在 Corda 中拥有负数额，因为您不能支付负余额或将负余额存入帐户。

但是您可以发布义务 (iou)，您可以在此处查看 r3 Corda 示例：https://github.com/roger3cev/obligation-cordapp

Answer 2

Amount 旨在不允许负数。以下 init 块阻止这样做：

init {
    // Amount represents a static balance of physical assets as managed by the distributed ledger and is not allowed
    // to become negative a rule further maintained by the Contract verify method.
    // N.B. If concepts such as an account overdraft are required this should be modelled separately via Obligations,
    // or similar second order smart contract concepts.
    require(quantity >= 0) { "Negative amounts are not allowed: $quantity" }
}

AmountTransfer 可用于对负迁移建模。或者，您可以简单地制作排除此 init 块的 Amount class 的副本。

Amount class 中如何表示负数？

How can negative numbers be represented in the Amount class?

corda