如何创建StaticTableSchema
对于嵌套 bean(例如这里的 items
属性)?
data class Order(
var id: Long = 0L,
var items: List<OrderLineItem> = emptyList(),
…
)
data class OrderLineItem(
var id: Long = 0L,
var price: BigDecimal = 0.0.toBigDecimal(),
…
)
最佳答案
首先,为嵌套 bean 创建一个 TableSchema
实现。它可能是 StaticTableSchema
或 BeanTableSchema
:
val orderLineItemStaticTableSchema = TableSchema
.builder(OrderLineItem::class.java)
.newItemSupplier(::OrderLineItem)
.addAttribute(Long::class.java) {
it.name("id").getter(OrderLineItem::id::get).setter(OrderLineItem::id::set)
}
.addAttribute(BigDecimal::class.java) {
it.name("price").getter(OrderLineItem::price::get).setter(OrderLineItem::price::set)
}
.build()
// or
val orderLineItemBeanTableSchema = TableSchema.fromBean(OrderLineItem::class.java)
然后,将此架构实例与EnhancedType.documentOf()
一起使用:
val tableSchema = TableSchema
.builder(Order::class.java)
.newItemSupplier(::Order)
.addAttribute(Long::class.java) {
it.name("id").getter(Order::id::get).setter(Order::id::set)
}
.addAttribute(
EnhancedType.listOf(
EnhancedType.documentOf(OrderLineItem::class.java, orderLineItemTableSchema)
)
) {
it.name("items").getter(Order::items::get).setter(Order::items::set)
}
.build()
关于amazon-web-services - 具有 StaticTableSchema 的嵌套 bean 和来自 AWS Java SDK 2.x 的增强型 DynamoDB 客户端,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/71573650/