OneToOne Unidirectional Support ------------------------------- Key: ANN-814 URL: http://opensource.atlassian.com/projects/hibernate/browse/ANN-814 Project: Hibernate Annotations Issue Type: Bug Affects Versions: 3.4.0.GA Environment: Oracle 10g, Java 1.5 Reporter: Rachit Priority: Blocker I tried hard for unidirectional OneToOne mapping as below: @Entity @Table(name = "PARTY") public class Party{ private Person person; private String key; @OneToOne(fetch = FetchType.EAGER, cascade = CascadeType.ALL,) @PrimaryKeyJoinColumn(name = "PARTY_ID", referencedColumnName = "PERSON_PARTY_ID") public Person getPerson() { return person; } public void setPerson(Person person) { this.person = person; } @Id @GeneratedValue(generator = "system-uuid") @GenericGenerator(name = "system-uuid", strategy = "uuid") @Column(name = "PARTY_ID", nullable = false) public String getKey() { return key; } private void setKey(String key) { this.key = key; } } and it is one-to-one mapped to Person as: @Entity(name = "Person") @Table(name = "PERSON") public class Person { private String key; @Id @Column(name = "PERSON_PARTY_ID") public String getKey() { return key; } public void setKey(String key) { this.key = key; } } Now in Person, I deliberately dont have sysUUID as generated as then it generates a unique value for person and the association gets lost. With this mapping hibernate throws the following exception : Caused by: org.hibernate.id.IdentifierGenerationException: ids for this class must be manually assigned before calling save(): Person. I read and saw constrained="true" being used in mapping files, which I couldnt use as there is no attribute like it in OneToOne annotation. Please help me out on this -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://opensource.atlassian.com/projects/hibernate/secure/Administrators.... - For more information on JIRA, see: http://www.atlassian.com/software/jira