CREATE SEQUENCE folder_id_seq START WITH 1;

CREATE TABLE folder (
  id BIGINT NOT NULL DEFAULT nextval('folder_id_seq'),
  tenantId VARCHAR(256) NOT NULL,
  PRIMARY KEY (id, tenantId)
);

CREATE TABLE folderTree (
    tenantId varchar,
    folderId bigint,
    parentId bigint,
    PRIMARY KEY (tenantId, folderId, parentId),
    FOREIGN KEY (tenantId, folderId) REFERENCES  folder (tenantId, id),
    FOREIGN KEY (tenantId, parentId) REFERENCES  folder (tenantId, id)
);

public class FolderId  implements Serializable {

    @Column
    private String tenantId;

    @Column
    private Long id;
    //equals, hashcode etc.
}

@Entity
@Table(name = "folder")
@IdClass(FolderId.class)
public class Folder {

    @Id
    @Column(name = "tenantId", updatable = false, nullable = false)
    private String tenantId;

    @Id
    @SequenceGenerator(name = "folder_id_seq", sequenceName = "folder_id_seq", allocationSize = 1)
    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "folder_id_seq")
    @Column(name = "id", updatable = false, nullable = false)
    private Long id;


    @OneToMany(mappedBy = "parent", cascade = CascadeType.ALL, orphanRemoval = true)
    private Set<Folder> children;


    @ManyToOne
    @JoinTable(name = "folderTree",
            joinColumns = {
                    @JoinColumn(name = "tenantId", referencedColumnName = "tenantId"),
                    @JoinColumn(name = "parentId", referencedColumnName = "id")
            },
            inverseJoinColumns = {
                    @JoinColumn(name = "tenantId", referencedColumnName = "tenantId"),
                    @JoinColumn(name = "folderId", referencedColumnName = "id")
            }
    )
    private Folder parent;
    //equals, hashcode etc.
}

Caused by: org.hibernate.MappingException: Repeated column in mapping for entity: com.example.demo.Folder column: tenantId (should be mapped with insert="false" update="false")
	at org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:862)
	at org.hibernate.mapping.PersistentClass.checkPropertyColumnDuplication(PersistentClass.java:880)
	at org.hibernate.mapping.PersistentClass.checkColumnDuplication(PersistentClass.java:908)
	at org.hibernate.mapping.PersistentClass.validate(PersistentClass.java:634)
	at org.hibernate.mapping.RootClass.validate(RootClass.java:267)
	at org.hibernate.boot.internal.MetadataImpl.validate(MetadataImpl.java:351)
	at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:464)
	at org.hibernate.jpa.boot.internal.EntityManagerFactoryBuilderImpl.build(EntityManagerFactoryBuilderImpl.java:1237)
	at org.springframework.orm.jpa.vendor.SpringHibernateJpaPersistenceProvider.createContainerEntityManagerFactory(SpringHibernateJpaPersistenceProvider.java:58)
	at org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean.createNativeEntityManagerFactory(LocalContainerEntityManagerFactoryBean.java:365)
	at org.springframework.orm.jpa.AbstractEntityManagerFactoryBean.buildNativeEntityManagerFactory(AbstractEntityManagerFactoryBean.java:391)
	... 83 more