QueryDSL子查询不工作-IllegalArgumentException：参数值与预期类型不匹配

Question

我试图在QueryDSL4.1.4中运行带有子查询的查询。版本3.x中的等价物起作用了，但我似乎无法在版本4.1.4中使其起作用。不确定是我漏了什么还是有个bug。感谢任何输入！

下面是相关代码：

PathBuilder productEntity = ...;
PathBuilder categoryEntity = ...;

JPQLQuery query = queryFactory.get().query();
query.distinct();

FilteredClause subQuery = JPAExpressions
    .select(productEntity.get("id", Long.class))
    .from(categoryEntity)
    .innerJoin(categoryEntity.get("products"), productEntity)
    .where(categoryEntity.get("id", Long.class).eq(categoryId));

query.where(productEntity.get("id", Long.class).notIn(subQuery));
query.fetch();

java.lang.IllegalArgumentException: Parameter value [select product.id
from Category category
  inner join treat(category.products as Product) as product
where category.id = ?1] did not match expected type [java.lang.Long (n/a)]
    at org.hibernate.jpa.spi.BaseQueryImpl.validateBinding(BaseQueryImpl.java:897)
    at org.hibernate.jpa.internal.QueryImpl.access$000(QueryImpl.java:61)
    at org.hibernate.jpa.internal.QueryImpl$ParameterRegistrationImpl.bindValue(QueryImpl.java:235)
    at org.hibernate.jpa.internal.QueryImpl$JpaPositionalParameterRegistrationImpl.bindValue(QueryImpl.java:371)
    at org.hibernate.jpa.spi.BaseQueryImpl.setParameter(BaseQueryImpl.java:692)
    at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:181)
    at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:32)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.lang.reflect.Method.invoke(Method.java:483)
    at org.springframework.orm.jpa.SharedEntityManagerCreator$DeferredQueryInvocationHandler.invoke(SharedEntityManagerCreator.java:372)
    at com.sun.proxy.$Proxy365.setParameter(Unknown Source)
    at com.querydsl.jpa.impl.JPAUtil.setConstants(JPAUtil.java:56)
    at com.querydsl.jpa.impl.AbstractJPAQuery.createQuery(AbstractJPAQuery.java:102)
    at com.querydsl.jpa.impl.AbstractJPAQuery.fetchCount(AbstractJPAQuery.java:81)
...

似乎整个子查询都被设置为参数，而Hibernate对此并不满意。是否应该使用不同的QueryDSL语法来避免此问题？

Answer 1

我发现问题是子查询的类型为filteredcluse。它没有导致任何编译错误，所以它可能是Querydsl可以更好地处理的东西，但是在将子查询更改为以下内容之后，就开始工作了：

JPQLQuery subQuery = JPAExpressions
    .select(productEntity.get("id", Long.class))
    .from(categoryEntity)
    .innerJoin(categoryEntity.get("products"), productEntity);

// Keep the .where() call separate to retain the JPQLQuery object
subQuery.where(categoryEntity.get("id", Long.class).eq(categoryId));

// subQuery is now of type JPQLQuery instead of FilteredClause
query.where(productEntity.get("id", Long.class).notIn(subQuery));

List result = query.fetch();