public class Legendtype implements Serializable {
    private static final long serialVersionUID = 1L;
    @Id   
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 100)
    @Column(nullable = false, length = 100)
    private String legendname;
    @Size(max = 500)
    @Column(name = "LEGEND_DESC", length = 500)
    private String legendDesc;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 50)
    @Column(nullable = false, length = 50)
    private String legendfor;
    @OneToMany(cascade = CascadeType.PERSIST, mappedBy = "legendnameFk", fetch = FetchType.LAZY)
    private List<Legend> legendList;
}

public class Legend implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)   
    private Integer sn;
    @Column(name = "LEGEND_SN")
    private Integer legendSn;
    @Basic(optional = false)
    @NotNull
    @Column(nullable = false)
    private double lowerrange;
    @Basic(optional = false)
    @NotNull
    @Column(nullable = false)
    private double upperrange;
    @Size(max = 500)
    @Column(name = "LEGEND_DESC", length = 500)
    private String legendDesc;
    @Size(max = 45)
    @Column(length = 45)
    private String color;
    @JoinColumn(name = "LEGENDNAME_FK", referencedColumnName = "LEGENDNAME", nullable = false)
    @ManyToOne(optional = false, fetch = FetchType.LAZY)
    private Legendtype legendnameFk;
}