Alina Ricciuti ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=61fb92a... ) *created* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiYzYzZDdiZTAz... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16215?atlOrigin=eyJpIjoiYzYzZD... ) HHH-16215 ( https://hibernate.atlassian.net/browse/HHH-16215?atlOrigin=eyJpIjoiYzYzZD... ) Composite primary key @IdClass attribute mapping is borrowed from the first OneToMany backref and cannot be set ( https://hibernate.atlassian.net/browse/HHH-16215?atlOrigin=eyJpIjoiYzYzZD... ) Issue Type: Bug Assignee: Unassigned Created: 21/Feb/2023 14:27 PM Environment: Hibernate: 6.1.7.Final, 6.2.0.CR2 Postgresql: 11 Spring Data JPA: 3.0.1 Spring Boot: 3.0.2 JDK: Oracle OpenJDK 17.0.2 OS: Windows 11 Priority: Major Reporter: Alina Ricciuti ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=61fb92a... ) Please find below the issue I have encountered during the migration from hibernate 5 to hibernante 6.1.7. My sample project is using Lombok / Spring Data; its datamodel is composed of : * Buckets having Lines @Getter @Setter @Entity @Table(name = "BUCKET") @SequenceGenerator(name = "SEQ_BUCKET_ID", allocationSize = 10, sequenceName = "SEQ_BUCKET_ID") @IdClass(PkBucket.class) public class Bucket { @Id @Column(name = "ID") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_BUCKET_ID") private Long id; @OneToMany(cascade = CascadeType.ALL) @JoinColumn(name = "BUCKET_ID", referencedColumnName = "id", nullable = false) private List<Line> lines = new ArrayList<>(); } * Items having Lines @Getter @Setter @Entity @Table(name = "LINE") @SequenceGenerator(name = "SEQ_LINE_ID", allocationSize = 10, sequenceName = "SEQ_LINE_ID") @IdClass(PkLine.class) public class Line { @Id @Column(name = "ID") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_LINE_ID") private Long id; @ManyToOne(targetEntity = Item.class) @JoinColumn(name = "ITEM_ID", referencedColumnName = "id", nullable = false) private Item item; } * The Line class @Getter @Setter @Entity @Table(name = "ITEM") @SequenceGenerator(name = "SEQ_ITEM_ID", allocationSize = 10, sequenceName = "SEQ_ITEM_ID") @IdClass(PkItem.class) public class Item { @Id @Column(name = "ID") @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "SEQ_ITEM_ID") private Long id; @OneToMany(mappedBy = "item", cascade = CascadeType.ALL, orphanRemoval = true) private List<Line> lines = new ArrayList<>(); } * The simplified Pk classes - they are all identical, as PkBucket here below @Getter @Setter public class PkBucket implements Serializable { private Long id; public PkBucket withId(Long id) { this.id = id; return this; } } My test is creating and updating some data : @Test @Transactional public void buckets_items_lines() { // create some data Session session = entityManager.unwrap(Session.class); session.createNativeQuery("insert into ITEM (id) values (100)").executeUpdate(); session.createNativeQuery("insert into ITEM (id) values (101)").executeUpdate(); session.createNativeQuery("insert into BUCKET (id) values (200)").executeUpdate(); session.createNativeQuery("insert into LINE (id, ITEM_ID, BUCKET_ID) values (300, 100, 200)").executeUpdate(); // move line from item to other item Item item100 = itemRepository.findById(new PkItem().withId(100L)).get(); final Item item101 = itemRepository.findById(new PkItem().withId(101L)).get(); item100.getLines().forEach(line -> line.setItem(item101)); } The issue below occurs when tying to hydrate Item.lines: Could not set value of type [java.lang.Long] : `com.example.demo.domain.issue2.PkBucket.id` (setter) org.hibernate.PropertyAccessException: Could not set value of type [java.lang.Long] : `com.example.demo.domain.issue2.PkBucket.id` (setter) at app//org.hibernate.property.access.spi.SetterFieldImpl.set(SetterFieldImpl.java:81) at app//org.hibernate.metamodel.mapping.internal.AbstractEmbeddableMapping.setValues(AbstractEmbeddableMapping.java:103) Few remarks: * As you can see in the stack attached, the Line property id is accessed through PkBucket id instead of PkLine id. * If I remove nullable = false from Bucket lines JoinColums the result is OK * If I use unique Pk class the issue persists : IllegalArgumentException: Can not set java.lang.Long field com.example.demo.domain.issue2.Pk.id ( http://com.example.demo.domain.issue2.Pk.id ) to com.example.demo.domain.issue2.Line * If I force the Line class to extend the expected id class the result is OK but this is not nice 🙂 ... @IdClass(PkLine.class) public class Line extends PkBucket { ... I have attached the full log; if needed, I can also share my sample project. ( https://hibernate.atlassian.net/browse/HHH-16215#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16215#add-comment?atlOrigin=ey... ) Get Jira notifications on your phone! Download the Jira Cloud app for Android ( https://play.google.com/store/apps/details?id=com.atlassian.android.jira.... ) or iOS ( https://itunes.apple.com/app/apple-store/id1006972087?pt=696495&ct=Em... ) This message was sent by Atlassian Jira (v1001.0.0-SNAPSHOT#100216- sha1:64a4cf6 )