Spring数据JPA通过嵌入对象属性找到。

I want to write a Spring Data JPA repository interface method signature that will let me find entities with a property of an embedded object in that entity. Does anyone know if this is possible, and if so how?

我想编写一个Spring Data JPA repository接口方法签名，它将让我在该实体中找到具有嵌入对象属性的实体。有谁知道这是否可能，如果是，如何?

Here's my code:

这是我的代码:

@Entity
@Table(name = "BOOK_UPDATE_QUEUE", indexes = { uniqueConstraints = @UniqueConstraint(columnNames = {
        "bookId", "region" }, name = "UK01_BOOK_UPDATE_QUEUE"))
public class QueuedBook implements Serializable {

    @Embedded
    @NotNull
    private BookId bookId;

    ...

}

@Embeddable
public class BookId implements Serializable {

    @NotNull
    @Size(min=1, max=40)
    private String bookId;

    @NotNull
    @Enumerated(EnumType.STRING)
    private Region region;

    ...

}

public interface QueuedBookRepo extends JpaRepository<QueuedBook, Long> {

    //I'd like to write a method like this, but can't figure out how to search by region,
    //when region is actually a part of the embedded BookId
    Page<QueuedBook> findByRegion(Region region, Pageable pageable);

}

Can I write a query for this using Spring Data?

我能用Spring数据编写查询吗?

3 个解决方案

#1

This method name should do the trick:

这个方法的名称应该可以做到:

Page<QueuedBook> findByBookIdRegion(Region region, Pageable pageable);

More info on that in the section about query derivation of the reference docs.

关于参考文档的查询派生部分的更多信息。

#2

The above - findByBookIdRegion() did not work for me. The following works with the latest release of String Data JPA:

以上- findByBookIdRegion()对我不起作用。以下是最新发布的字符串数据JPA:

Page<QueuedBook> findByBookId_Region(Region region, Pageable pageable);

#3

If you are using BookId as an combined primary key, then remember to change your interface from:

如果您使用BookId作为组合主键，那么请记住更改您的接口:

public interface QueuedBookRepo extends JpaRepository<QueuedBook, Long> {

to:

public interface QueuedBookRepo extends JpaRepository<QueuedBook, BookId> {

And change the annotation @Embedded to @EmbeddedId, in your QueuedBook class like this:

并将@嵌入到@Embedded dedid中，在您的QueuedBook类中:

public class QueuedBook implements Serializable {

@EmbeddedId
@NotNull
private BookId bookId;

...

}

#1