Hibernate 中的 JPA root 无法使用 IdClass 属性
我正在尝试对具有 IdClass 的实体进行多重选择。我无法获取映射为 ID 一部分的列。很明显为什么我不能,因为标记为 @Ids 的列都不是 hibernate 正在创建的 EntityType 中属性的一部分,它们是 IdAttributes 映射的一部分。
这段代码在 openJPA 中运行良好,但由于各种原因我决定转向休眠。
失败的代码:
CriteriaBuilder queryBuilder = getEntityManager().getCriteriaBuilder();
CriteriaQuery<Tuple> query = queryBuilder.createTupleQuery();
Root<ProductSearchFilter> productSearchFilterRoot = query.from(ProductSearchFilter.class);
query.multiselect(productSearchFilterRoot.get("productId").alias("productId"),
productSearchFilterRoot.get("category").alias("category"),
productSearchFilterRoot.get("name").alias("name"),
productSearchFilterRoot.get("fdaStatus").alias("fdaStatus"));
query.distinct(true);
错误:
java.lang.IllegalArgumentException: Unable to resolve attribute [productId] against path
我的映射设置:
@Table(name = "PRODUCT_SEARCH_FILTER")
@Entity()
@IdClass(ProductSearchFilterPK.class)
public class ProductSearchFilter {
private String source;
private String productId;
private String name;
private String category;
private String searchColumn;
private String fdaStatus;
@Column(name = "SOURCE", length = 11)
public String getSource() {
return source;
}
public void setSource(String source) {
this.source = source;
}
@Column(name = "PRODUCT_ID", length = 46, insertable = false, updatable = false)
@Id
public String getProductId() {
return productId;
}
public void setProductId(String productId) {
this.productId = productId;
}
@Column(name = "NAME", length = 510)
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Column(name = "CATEGORY", length = 10)
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
@Column(name = "SEARCH_COLUMN", length = 1088, insertable = false, updatable = false)
@Id
public String getSearchColumn() {
return searchColumn;
}
public void setSearchColumn(String searchColumn) {
this.searchColumn = searchColumn;
}
@Column(name = "FDA_STATUS", insertable = false, updatable = false)
@Id
public String getFdaStatus() {
return fdaStatus;
}
public void setFdaStatus(String fdaStatus) {
this.fdaStatus = fdaStatus;
}
}
public class ProductSearchFilterPK implements Serializable {
private String productId;
private String searchColumn;
private String fdaStatus;
public String getFdaStatus() {
return fdaStatus;
}
public void setFdaStatus(String fdaStatus) {
this.fdaStatus = fdaStatus;
}
public String getProductId() {
return productId;
}
public void setProductId(String productId) {
this.productId = productId;
}
public String getSearchColumn() {
return searchColumn;
}
public void setSearchColumn(String searchColumn) {
this.searchColumn = searchColumn;
}
}
I'm trying to do a multiselect on an entity with an IdClass. I can't get a column that is mapped as part of the ID. It's clear why I can't, as none of the columns that are marked as @Ids are a part of the attributes in the EntityType that hibernate is creating, they are a part of the IdAttributes map.
This bit of code worked fine in openJPA, but I've decided to make the move to hibernate for various reasons.
The code that fails:
CriteriaBuilder queryBuilder = getEntityManager().getCriteriaBuilder();
CriteriaQuery<Tuple> query = queryBuilder.createTupleQuery();
Root<ProductSearchFilter> productSearchFilterRoot = query.from(ProductSearchFilter.class);
query.multiselect(productSearchFilterRoot.get("productId").alias("productId"),
productSearchFilterRoot.get("category").alias("category"),
productSearchFilterRoot.get("name").alias("name"),
productSearchFilterRoot.get("fdaStatus").alias("fdaStatus"));
query.distinct(true);
The error:
java.lang.IllegalArgumentException: Unable to resolve attribute [productId] against path
My Mapping setup:
@Table(name = "PRODUCT_SEARCH_FILTER")
@Entity()
@IdClass(ProductSearchFilterPK.class)
public class ProductSearchFilter {
private String source;
private String productId;
private String name;
private String category;
private String searchColumn;
private String fdaStatus;
@Column(name = "SOURCE", length = 11)
public String getSource() {
return source;
}
public void setSource(String source) {
this.source = source;
}
@Column(name = "PRODUCT_ID", length = 46, insertable = false, updatable = false)
@Id
public String getProductId() {
return productId;
}
public void setProductId(String productId) {
this.productId = productId;
}
@Column(name = "NAME", length = 510)
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
@Column(name = "CATEGORY", length = 10)
public String getCategory() {
return category;
}
public void setCategory(String category) {
this.category = category;
}
@Column(name = "SEARCH_COLUMN", length = 1088, insertable = false, updatable = false)
@Id
public String getSearchColumn() {
return searchColumn;
}
public void setSearchColumn(String searchColumn) {
this.searchColumn = searchColumn;
}
@Column(name = "FDA_STATUS", insertable = false, updatable = false)
@Id
public String getFdaStatus() {
return fdaStatus;
}
public void setFdaStatus(String fdaStatus) {
this.fdaStatus = fdaStatus;
}
}
public class ProductSearchFilterPK implements Serializable {
private String productId;
private String searchColumn;
private String fdaStatus;
public String getFdaStatus() {
return fdaStatus;
}
public void setFdaStatus(String fdaStatus) {
this.fdaStatus = fdaStatus;
}
public String getProductId() {
return productId;
}
public void setProductId(String productId) {
this.productId = productId;
}
public String getSearchColumn() {
return searchColumn;
}
public void setSearchColumn(String searchColumn) {
this.searchColumn = searchColumn;
}
}
有一个解决方法,那就是使用规范元模型。
不幸的是,我们从productSearchFilterRoot获得的EntityModel对我们没有多大帮助,因为它
只给我们一个集合的视图。因此,我们无法立即通过属性名称查询 IdClass 的属性。
但无论如何,它们就在那里:
相反,我们将采用规范元模型。为此,我们需要一个可以实现的新类
我们自己,或者让 Hibenate 来做:
然后我们将使用 ProductSearchFilter_ 的字段作为参数来获取 ProductSearchFilterRoot:
因为我们现在有了元模型,我也用它来创建名称选择,但因为那个不是 id 的一部分,我们可以保持原样:
There is workaround, which is using canonical metamodel.
Unfortunately EntityModel we get from productSearchFilterRoot does not help us much, because it
only gives us view as a set. So we cannot query Attributes of IdClass right away by name of attribute from there.
But there they are anyway:
Instead we we will go for canonical metamodel. For that we need one new class which we can implement
by ourselves, or let Hibenate do it:
And then we will use fields of ProductSearchFilter_ as argument to get in productSearchFilterRoot:
Because we now have metamodel, I used it also to create selection for name, but because that one is not part of id, we could have left it as it was: