@MappedSuperclass
public class BaseEntity implements Serializable {

    @Id
    @Column(name = "ID", unique = true)
    @Size(min = 1, max = 255)
    private String id;

    @PrePersist
    public final void generateUuid() {
        if (this.getId() == null) {
            this.setId(UUID.randomUUID().toString());
        }
    }

    public final String getId() {
        return id;
    }

    public final void setId(final String id) {
        this.id = id;
    }
}

@Entity
@Audited
public class AidConfiguration extends BaseEntity {

    @Column
    @NotBlank
    private String name;

    @NotNull
    @ManyToOne(fetch = FetchType.LAZY) // if it is EAGER (defaut) then then aidConfiguration.getChipApplication().getId() returns correctly non-null value
    private ChipApplication chipApplication;

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "aidConfiguration", cascade = CascadeType.ALL) // cascade for auto-saving and deleting items
    private List<AidConfigurationItem> aidConfigurationItems;

    public String getName() {
        return name;
    }

    public void setName(final String name) {
        this.name = name;
    }

    public ChipApplication getChipApplication() {
        return chipApplication;
    }

    public void setChipApplication(final ChipApplication chipApplication) {
        this.chipApplication = chipApplication;
    }

    public List<AidConfigurationItem> getAidConfigurationItems() {
        return aidConfigurationItems;
    }

    public void setAidConfigurationItems(final List<AidConfigurationItem> aidConfigurationItems) {
        this.aidConfigurationItems = aidConfigurationItems;
    }
}

@Entity
@Audited
public class ChipApplication extends BaseEntity {

    @Column
    @NotBlank(message = "Aid can not be empty")
    private String aid;

    @Column
    @NotBlank(message = "Product can not be empty")
    private String product;

    @Column
    @NotBlank(message = "Version can not be empty")
    private String version;

    @NotNull(message = "Network is mandatory")
    @ManyToOne(fetch = FetchType.LAZY)
    private Network network;

    @ManyToMany(fetch =  FetchType.EAGER)
    private List<AidTag> aidTags;

    public String getAid() {
        return aid;
    }

    public void setAid(final String aid) {
        this.aid = aid;
    }

    public String getProduct() {
        return product;
    }

    public void setProduct(final String product) {
        this.product = product;
    }

    public String getVersion() {
        return version;
    }

    public void setVersion(final String version) {
        this.version = version;
    }

    public Network getNetwork() {
        return network;
    }

    public void setNetwork(final Network network) {
        this.network = network;
    }

    public List<AidTag> getAidTags() {
        return aidTags;
    }

    public void setAidTags(final List<AidTag> aidTags) {
        this.aidTags = aidTags;
    }
}