Question

spring Data jpa 一对多关联 动态查询怎么写

请问看得懂java代码吗多表联查动态查询 能实现吗。barCode是子表的条件
Commodity实体类有个 commodityBarcodes；
CommodityBarcode里有个barCode条件
@OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "commodity")
private List<CommodityBarcode> commodityBarcodes;
dao层继承JpaSpecificationExecutor有个findAll（Specification
<e>, Page<e>）方法

Specification接口里怎么动态拼接子表的搜索条件

Answer 1

predicates.add(cb.like(root.get("commodityBarcodes").get("barCode"), "%" + dto.getBarCode() + "%"));

你试试这样写，我用@OneToOne就是这么写的。感觉这样也差不多

追问

我是@OneToMany
像你这样写会报错
Illegal attempt to dereference path source [null.commodityBarcodes] of basic type; nested exception is java.lang.IllegalStateException: Illegal attempt to dereference path source [null.commodityBarcodes] of basic type