HHH-13815 - TransientObjectException when merging a bidirectional one-to-many with orphan delete

[lisandrofernandez]

Add test case to replicate the issue.

https://hibernate.atlassian.net/browse/HHH-13815

[gavinking]

Here's an updated test which fails on H7.

package org.hibernate.userguide.associations;

import org.hibernate.testing.orm.junit.JiraKey;
import org.junit.Before;
import org.junit.Test;

import jakarta.persistence.CascadeType;
import jakarta.persistence.Entity;
import jakarta.persistence.FetchType;
import jakarta.persistence.GeneratedValue;
import jakarta.persistence.GenerationType;
import jakarta.persistence.Id;
import jakarta.persistence.JoinColumn;
import jakarta.persistence.ManyToOne;
import jakarta.persistence.OneToMany;
import java.util.ArrayList;
import java.util.List;

import static org.hibernate.testing.transaction.TransactionUtil.doInJPA;

/**
 * @author Lisandro Fernandez (kelechul at gmail dot com)
 */
@JiraKey("HHH-13815")
public class BidirectionalOneToManyMergeTest extends org.hibernate.orm.test.jpa.BaseEntityManagerFunctionalTestCase {

	@Override
	protected Class<?>[] getAnnotatedClasses() {
		return new Class<?>[]{
				Post.class,
				PostComment.class,
		};
	}

	@Before
	public void setUp() {
		doInJPA(this::entityManagerFactory, entityManager -> {
			entityManager.persist(
					new Post("High-Performance Java Persistence").setId(1L)
			);
		});
	}

	@Test
	public void testFailMerge() {
		doInJPA(this::entityManagerFactory, entityManager -> {
			Post post = entityManager.find(Post.class, 1L);
			post.addComment(new PostComment("This post rocks!", post));
			post.getComments().isEmpty(); // this fails
			entityManager.merge(post);
		});
	}

	@Entity
	public static class Post {

		@Id
		private Long id;

		private String title;

		@OneToMany(mappedBy = "post", cascade = CascadeType.ALL, orphanRemoval = true)
		private List<PostComment> comments = new ArrayList<>();

		public Post() {
		}

		public Post(String title) {
			this.title = title;
		}

		public Long getId() {
			return id;
		}

		public Post setId(Long id) {
			this.id = id;
			return this;
		}

		public String getTitle() {
			return title;
		}

		public Post setTitle(String title) {
			this.title = title;
			return this;
		}

		public List<PostComment> getComments() {
			return comments;
		}

		private Post setComments(List<PostComment> comments) {
			this.comments = comments;
			return this;
		}

		public Post addComment(PostComment comment) {
			comments.add(comment);
			comment.setPost(this);

			return this;
		}

		public Post removeComment(PostComment comment) {
			comments.remove(comment);
			comment.setPost(null);

			return this;
		}
	}

	@Entity
	public static class PostComment {

		@Id
		@GeneratedValue(strategy = GenerationType.IDENTITY)
		private Long id;

		private String review;

		@ManyToOne(fetch = FetchType.LAZY)
		@JoinColumn(name = "post_id")
		private Post post;

		public PostComment() {
		}

		public PostComment(String review, Post post) {
			this.review = review;
			this.post = post;
		}

		public Long getId() {
			return id;
		}

		public PostComment setId(Long id) {
			this.id = id;
			return this;
		}

		public String getReview() {
			return review;
		}

		public PostComment setReview(String review) {
			this.review = review;
			return this;
		}

		public Post getPost() {
			return post;
		}

		public PostComment setPost(Post post) {
			this.post = post;
			return this;
		}

		@Override
		public boolean equals(Object o) {
			if (this == o) return true;
			if (!(o instanceof PostComment)) return false;
			return id != null && id.equals(((PostComment) o).getId());
		}

		@Override
		public int hashCode() {
			return 31;
		}
	}
}

We should fix this; it looks fairly straightforward. (Just disable the exception when processing orphan delete.)

[dreab8]

superseded by #9420