annotations_mapped_superclass

Father's class

---

  @MappedSuperclass
  public class Worker implements Serializable {

  @Column
  private String name;

  @Column
  private Double salary;

  //getter and setter

 }

---

child's class

---

  @Entity
  public class Engineer extends Worker {

  @Id
  private String nickName;

  @Column
  private String type;

  @Column
  private String especialization;

  //getter and setter

 }

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