@Entity
@Table(name = "operation")
public class Operation implements Serializable {

 @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "id")
    private Long id;

    @Column(name = "created_by")
    private String createdBy;

    @Column(name = "object_name")
    private String objectName;

    @Column(name = "action")
    @Enumerated(EnumType.STRING)
    private OperationType action;

    @CreatedDate
    @Column(name = "created_date")
    @Temporal(TemporalType.TIMESTAMP)
    private Date createdDate;

public enum OperationType {
    OK, CREATE, READ, UPDATE, DELETE, ERROR, PREPERSIST, PREUPDATE, POSTPERSIST, POSTUPDATE , PREDELETE, POSTDELETE ;
}