@Entity
@Table(name = "USERS")
public class User implements Serializable
{
  @Id
  @Column(name = "USER_ID", nullable = false, length = 10)
  private String userId;
  @Column(name = "NAME_AT_BIRTH", nullable = false)
  private String nameAtBirth;
  @Column(name = "LAST_NAME", nullable = false)
  private String lastName;
  @Column(name = "FIRST_NAME", nullable = false)
  private String firstName;
  @Column(name = "MOTHERS_NAME", nullable = false)
  private String mothersName;
  @Column(name = "PERM_ADDRESS", nullable = false)
  private String permAddress;
  @Column(name = "TEMP_ADDRESS")
  private String tempAddress;
  @Temporal(value = TemporalType.DATE)
  @Column(name = "BIRTHDATE", nullable = false, length = 7)
  private Date birthdate;
  @Column(name = "PASSWORD", nullable = false, length = 32)
  private String password;
  @Column(name = "EMAIL", length = 320)
  private String email;
  @Temporal(value = TemporalType.DATE)
  @Column(name = "START_DATE", nullable = false, length = 7)
  private Date startDate;
  @Temporal(value = TemporalType.DATE)
  @Column(name = "END_DATE", length = 7)
  private Date endDate;
  @Column(name = "TYPE", length = 16)
  private String type;
  @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "user")
  private List<UserCheck> checks = new ArrayList<UserCheck>();
  @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "user")
  private List<UserCurse> curses = new ArrayList<UserCurse>();
}

@Entity
@Table(name = "CURSES")
public class Curse implements Serializable
{
  @EmbeddedId
  @AttributeOverrides(
  {
    @AttributeOverride(name = "curseId", column = @Column(name = "CURSE_ID", nullable = false, length = 16)),
    @AttributeOverride(name = "semesterId", column = @Column(name = "SEMESTER_ID", nullable = false, length = 10))
  })
  private CurseId id;
  @ManyToOne(fetch = FetchType.LAZY)
  @JoinColumn(name = "SEMESTER_ID", nullable = false, insertable = false, updatable = false)
  private Semester semester;
  @ManyToOne(fetch = FetchType.LAZY)
  @JoinColumn(name = "ROOM_ID", nullable = true)
  private Room room;
  @ManyToOne(fetch = FetchType.LAZY)
  @JoinColumn(name = "SUBJECT_ID", nullable = false)
  private Subject subject;
  @Column(name = "TIME", nullable = true, length = 32)
  private String time;
  @Column(name = "STUDENTS_LIMIT", precision = 10, scale = 0, nullable = true)
  private Long studentsLimit;
  @OneToOne
  @JoinColumns(value =
  {
    @JoinColumn(name = "CURSE_ID", referencedColumnName = "CURSE_ID", nullable = false, insertable = false, updatable = false),
    @JoinColumn(name = "SEMESTER_ID", referencedColumnName = "SEMESTER_ID", nullable = false, insertable = false, updatable = false)
  })
  private CurseUserCountView curseUserCountView;
  @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "curse")
  private List<UserCurse> users = new ArrayList<UserCurse>();
  @OneToMany(cascade = CascadeType.ALL, fetch = FetchType.LAZY, mappedBy = "curse")
  private List<Check> checks = new ArrayList<Check>();
}

@Embeddable
public class CurseId implements Serializable
{
  @Column(name = "CURSE_ID", nullable = false, length = 16)
  private String curseId;
  @Column(name = "SEMESTER_ID", nullable = false, length = 10)
  private String semesterId;
}

@Entity
@Table(name = "USERS_CURSES")
public class UserCurse implements Serializable
{
  @EmbeddedId
  @AttributeOverrides(
  {
    @AttributeOverride(name = "userId", column = @Column(name = "USER_ID", nullable = false, length = 16)),
    @AttributeOverride(name = "curseId", column = @Column(name = "CURSE_ID", nullable = false, length = 16)),
    @AttributeOverride(name = "semesterId", column = @Column(name = "SEMESTER_ID", nullable = false, length = 10))
  })
  private UserCurseId id;
  @ManyToOne(fetch = FetchType.LAZY)
  @JoinColumn(name = "USER_ID", nullable = false, insertable = false, updatable = false)
  private User user;
  @ManyToOne(fetch = FetchType.LAZY)
  @JoinColumns(value =
  {
    @JoinColumn(name = "CURSE_ID", referencedColumnName = "CURSE_ID", nullable = false, insertable = false, updatable = false),
    @JoinColumn(name = "SEMESTER_ID", referencedColumnName = "SEMESTER_ID", nullable = false, insertable = false, updatable = false)
  })
  private Curse curse;
  @Column(name = "PERFORMED", precision = 1, scale = 0)
  private Boolean performed;
}

@Embeddable
public class UserCurseId implements Serializable
{
  @Column(name = "USER_ID", nullable = false, length = 16)
  private String userId;
  @Column(name = "CURSE_ID", nullable = false, length = 16)
  private String curseId;
  @Column(name = "SEMESTER_ID", nullable = false, length = 10)
  private String semesterId;
}