Nick V ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) *updated* an issue Hibernate ORM ( https://hibernate.atlassian.net/browse/HHH?atlOrigin=eyJpIjoiYTk0MmFhYjhm... ) / Bug ( https://hibernate.atlassian.net/browse/HHH-16948?atlOrigin=eyJpIjoiYTk0Mm... ) HHH-16948 ( https://hibernate.atlassian.net/browse/HHH-16948?atlOrigin=eyJpIjoiYTk0Mm... ) TimestampMutabilityPlan breaks entity's equals() ( https://hibernate.atlassian.net/browse/HHH-16948?atlOrigin=eyJpIjoiYTk0Mm... ) Change By: Nick V ( https://hibernate.atlassian.net/secure/ViewProfile.jspa?accountId=557058%... ) TimestampMutabilityPlan [returns|https://github.com/hibernate/hibernate-orm/blob/6.2.5/hibernate-c...] java.sql.Timestamp which breaks equals(). Entity: {code:java}package com.example.demobug; import jakarta.persistence.Entity; import jakarta.persistence.Id; import jakarta.persistence.Temporal; import jakarta.persistence.TemporalType; import lombok.Data; import lombok.NoArgsConstructor; import java.util.Date; import java.util.UUID; @Entity @NoArgsConstructor @Data public class Company { @Id private UUID id; @Temporal(TemporalType.TIMESTAMP) private Date establishedAt; } {code} Test. {code:java}package com.example.demobug; import org.junit.jupiter.api.Test; import org.springframework.beans.factory.annotation.Autowired; import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest; import org.springframework.boot.test.autoconfigure.orm.jpa.TestEntityManager; import java.util.Date; import java.util.UUID; import static org.assertj.core.api.Assertions.assertThat; @DataJpaTest class CompanyTest { @Autowired public TestEntityManager entityManager; @Test void shouldSaveEntity() { final Company company = createNewCompany(); final Company found = entityManager.find(Company.class, company.getId()); assertThat(found.getId()).isEqualTo(company.getId()); assertThat(found.getEstablishedAt()).isEqualTo(company.getEstablishedAt()); assertThat(found).isEqualTo(company); } private Company createNewCompany() { final Company company = new Company(); company.setId(UUID.randomUUID()); company.setEstablishedAt(new Date()); entityManager.persistAndFlush(company); entityManager.detach(company); entityManager.flush(); entityManager.clear(); return company; } }{code} Assertion error: {noformat}org.opentest4j.AssertionFailedError: expected: 2023-07-17T15:47:01.131 (java.util.Date) but was: 2023-07-17T15:47:01.131 (java.sql.Timestamp){noformat} ( https://hibernate.atlassian.net/browse/HHH-16948#add-comment?atlOrigin=ey... ) Add Comment ( https://hibernate.atlassian.net/browse/HHH-16948#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#100232- sha1:33a7c72 )