Hibernate Composite Key Using Annotation , Having One Foreign Key

Question

I googled it but could't found any solution

I Two classes Application.java and ApplicationVersion.java they have One-to-Many relation, ApplicationVersionPk.java is a Embedable class which is used as composite key in ApplicationVersionPk.java below are my classes when i run my web app i get Mapping Exception with

 nested exception is org.hibernate.MappingException: Foreign key (FKA50BD18824C3AEF5:ApplicationVersion [application_id,version])) must have same number of columns as the referenced primary key (Application [id]):

Application.java

@Entity
@Table(uniqueConstraints = @UniqueConstraint(columnNames = { "nameSpace" }))
public class Application implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private Long id;
    private Set<ApplicationVersion> appVersions = new HashSet<ApplicationVersion>(
            5);

    @Id
    @GeneratedValue
    public Long getId() {
        return id;
    }

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


    @OneToMany(fetch = FetchType.LAZY, mappedBy = "applicationVersionPk")

    @Cascade(value = { CascadeType.DELETE })
    public Set<ApplicationVersion> getAppVersions() {
        return appVersions;
    }

    public void setAppVersions(Set<ApplicationVersion> appVersions) {
        this.appVersions = appVersions;
    }

}

ApplicationVersion.java

@Entity
public class ApplicationVersion implements Serializable {

    private static final long serialVersionUID = 1L;
    private Long id;

    private ApplicationVersionPk applicationVersionPk;

        @EmbeddedId
    public ApplicationVersionPk getApplicationVersionPk() {
        return applicationVersionPk;
    }

    public void setApplicationVersionPk(
            ApplicationVersionPk applicationVersionPk) {
        this.applicationVersionPk = applicationVersionPk;
    }


    @GeneratedValue
    public Long getId() {
        return id;
    }

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

}

ApplicationVersionPk.java

@Embeddable
public class ApplicationVersionPk implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;

    private Application application;
    private String version;

    @ManyToOne(fetch = FetchType.LAZY)
    @JoinColumns({ @JoinColumn(referencedColumnName = "id", nullable = false) })
    public Application getApplication() {
        return application;
    }

    public void setApplication(Application application) {
        this.application = application;
    }

    public String getVersion() {
        return version;
    }

    public void setVersion(String version) {
        this.version = version;
    }

    public boolean equals(Object other) {
        if ((this == other))
            return true;
        if ((other == null))
            return false;
        if (!(other instanceof ApplicationVersionPk))
            return false;
        ApplicationVersionPk versionPk = (ApplicationVersionPk) other;

        return (this.getApplication().getNameSpace()
                .equalsIgnoreCase(versionPk.getApplication().getNameSpace()) && this.version
                .equalsIgnoreCase(versionPk.getVersion()));
    }

    public int hashCode() {
        int result = 17;

        result = result + this.version.hashCode();
        result += result + this.getApplication().getNameSpace().hashCode();
        return result;
    }

}

Answer 1

You are joining Application.appVersions using two keys on the side of ApplicationVersion instead of the only application's @Id; you can use mappedBy="applicationVersionPk.application"