当我使用IDEA新建一个休眠项目并使用mysql模式生成持久性映射时，抛出IllegalArgumentException

Question

我只是使用IDEA来创建一个休眠的项目，然后使用mysql模式生成持久性映射。 而且我想运行这些东西（它们是自动生成的），但是有一个错误和一个异常，我无法解决这些问题...

java.lang.ExceptionInInitializerError
    at HibernateSessionFactory.<clinit>(HibernateSessionFactory.java:31)
Caused by: java.lang.IllegalArgumentException: expecting IdClass mapping

休眠5.4.2 MySQL 8.0.15

//----------------------------------------------------------
// GradesEntity.java
public class HibernateSessionFactory {
    private static final SessionFactory ourSessionFactory;
    static {
        try {
            Configuration configuration = new Configuration();
            configuration.configure();
            configuration.addClass(CourseEntity.class)
                    .addClass(GradesEntity.class)
                    .addClass(GradesTypeEntity.class)
                    .addClass(GroupEntity.class)
                    .addClass(PersonResponsibleEntity.class)
                    .addClass(ProfessorEntity.class)
                    .addClass(ResponsibleEntity.class)
                    .addClass(StudentEntity.class)
                    .addClass(TeachingEntity.class);
            ourSessionFactory = configuration.buildSessionFactory();
        } catch (Throwable ex) {
            throw new ExceptionInInitializerError(ex);
        }
    }

    public static void main(final String[] args) throws Exception {

        final Session session = getSession();
        try {
            System.out.println("querying all the managed entities...");
            final Metamodel metamodel = session.getSessionFactory().getMetamodel();
            for (EntityType<?> entityType : metamodel.getEntities()) {
                final String entityName = entityType.getName();
                final Query query = session.createQuery("from " + entityName);
                System.out.println("executing: " + query.getQueryString());
                for (Object o : query.list()) {
                    System.out.println("  " + o);
                }
            }
        } finally {
            session.close();
        }
    }

    public static Session getSession() throws HibernateException {
        return ourSessionFactory.openSession();
    }
}

//----------------------------------------------------------
// GradesEntity.java
@Entity
@Table(name = "grades", schema = "bdd2_projet", catalog = "")
@IdClass(GradesEntityPK.class)
public class GradesEntity {
    private int idStudent;
    private int codeCourse;
    private Integer grades;
    private int idProfessor;

    @Id
    @Column(name = "id_student", nullable = false)
    public int getIdStudent() {
        return idStudent;
    }

    public void setIdStudent(int idStudent) {
        this.idStudent = idStudent;
    }

    @Id
    @Column(name = "code_course", nullable = false)
    public int getCodeCourse() {
        return codeCourse;
    }

    public void setCodeCourse(int codeCourse) {
        this.codeCourse = codeCourse;
    }

    @Basic
    @Column(name = "grades", nullable = true)
    public Integer getGrades() {
        return grades;
    }

    public void setGrades(Integer grades) {
        this.grades = grades;
    }

    @Id
    @Column(name = "id_professor", nullable = false)
    public int getIdProfessor() {
        return idProfessor;
    }

    public void setIdProfessor(int idProfessor) {
        this.idProfessor = idProfessor;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        GradesEntity that = (GradesEntity) o;
        return idStudent == that.idStudent &&
                codeCourse == that.codeCourse &&
                idProfessor == that.idProfessor &&
                Objects.equals(grades, that.grades);
    }

    @Override
    public int hashCode() {
        return Objects.hash(idStudent, codeCourse, grades, idProfessor);
    }
}

//----------------------------------------------------------
// GradesEntityPK.java
public class GradesEntityPK implements Serializable {
    private int idStudent;
    private int codeCourse;
    private int idProfessor;

    @Id
    @Column(name = "id_student", nullable = false)
    public int getIdStudent() {
        return idStudent;
    }

    public void setIdStudent(int idStudent) {
        this.idStudent = idStudent;
    }

    @Id
    @Column(name = "code_course", nullable = false)
    public int getCodeCourse() {
        return codeCourse;
    }

    public void setCodeCourse(int codeCourse) {
        this.codeCourse = codeCourse;
    }

    @Id
    @Column(name = "id_professor", nullable = false)
    public int getIdProfessor() {
        return idProfessor;
    }

    public void setIdProfessor(int idProfessor) {
        this.idProfessor = idProfessor;
    }

    @Override
    public boolean equals(Object o) {
        if (this == o) return true;
        if (o == null || getClass() != o.getClass()) return false;
        GradesEntityPK that = (GradesEntityPK) o;
        return idStudent == that.idStudent &&
                codeCourse == that.codeCourse &&
                idProfessor == that.idProfessor;
    }

    @Override
    public int hashCode() {
        return Objects.hash(idStudent, codeCourse, idProfessor);
    }
}

针尖上的错误和兴奋：

java.lang.ExceptionInInitializerError
    at HibernateSessionFactory.<clinit>(HibernateSessionFactory.java:31)
Caused by: java.lang.IllegalArgumentException: expecting IdClass mapping
    at org.hibernate.metamodel.internal.AttributeFactory$3.resolveMember(AttributeFactory.java:977)
    at org.hibernate.metamodel.internal.AttributeFactory$5.resolveMember(AttributeFactory.java:1035)
    at org.hibernate.metamodel.internal.AttributeFactory.determineAttributeMetadata(AttributeFactory.java:450)
    at org.hibernate.metamodel.internal.AttributeFactory.buildIdAttribute(AttributeFactory.java:139)
    at org.hibernate.metamodel.internal.MetadataContext.buildIdClassAttributes(MetadataContext.java:389)
    at org.hibernate.metamodel.internal.MetadataContext.applyIdMetadata(MetadataContext.java:319)
    at org.hibernate.metamodel.internal.MetadataContext.wrapUp(MetadataContext.java:222)
    at org.hibernate.metamodel.internal.MetamodelImpl.initialize(MetamodelImpl.java:274)
    at org.hibernate.internal.SessionFactoryImpl.<init>(SessionFactoryImpl.java:294)
    at org.hibernate.boot.internal.SessionFactoryBuilderImpl.build(SessionFactoryBuilderImpl.java:462)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:708)
    at org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:724)
    at HibernateSessionFactory.<clinit>(HibernateSessionFactory.java:29)
Exception in thread "main"