Question

我使用此向导从我的数据库创建实体类。有些表尚未转换为类，但有一些属性可以识别关系。

这是用户实体类（属性）

@Entity
@Table(name = "user")
@XmlRootElement
@NamedQueries({
    @NamedQuery(name = "User.findAll", query = "SELECT u FROM User u"),
    @NamedQuery(name = "User.findByOid", query = "SELECT u FROM User u WHERE u.oid = :oid"),
    @NamedQuery(name = "User.findByUsername", query = "SELECT u FROM User u WHERE u.username = :username"),
    @NamedQuery(name = "User.findByPassword", query = "SELECT u FROM User u WHERE u.password = :password"),
    @NamedQuery(name = "User.findByEmail", query = "SELECT u FROM User u WHERE u.email = :email"),
    @NamedQuery(name = "User.findByAddress", query = "SELECT u FROM User u WHERE u.address = :address"),
    @NamedQuery(name = "User.findBySince", query = "SELECT u FROM User u WHERE u.since = :since")})
public class User implements Serializable {

    private static final long serialVersionUID = 1L;
    @Id
    @GeneratedValue(strategy = GenerationType.IDENTITY)
    @Basic(optional = false)
    @Column(name = "oid")
    private Integer oid;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 15)
    @Column(name = "username")
    private String username;
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 15)
    @Column(name = "password")
    private String password;
    // @Pattern(regexp="[a-z0-9!#$%&'*+/=?^_`{|}~-]+(?:\\.[a-z0-9!#$%&'*+/=?^_`{|}~-]+)*@(?:[a-z0-9](?:[a-z0-9-]*[a-z0-9])?\\.)+[a-z0-9](?:[a-z0-9-]*[a-z0-9])?", message="Invalid email")//if the field contains email address consider using this annotation to enforce field validation
    @Basic(optional = false)
    @NotNull
    @Size(min = 1, max = 30)
    @Column(name = "email")
    private String email;
    @Size(max = 50)
    @Column(name = "address")
    private String address;
    @Basic(optional = false)
    @NotNull
    @Column(name = "since")
    @Temporal(TemporalType.DATE)
    private Date since;
    @JoinTable(name = "favorite", joinColumns = {
        @JoinColumn(name = "user_oid", referencedColumnName = "oid")}, inverseJoinColumns = {
        @JoinColumn(name = "wheelchair_oid", referencedColumnName = "oid")})
    @ManyToMany
    private List<Wheelchair> wheelchairList;
    @ManyToMany(mappedBy = "userList1")
    private List<Wheelchair> wheelchairList1;
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "senderOid")
    private List<Comment> commentList;
    @JoinColumn(name = "role_oid", referencedColumnName = "oid")
    @ManyToOne(optional = false)
    private Role roleOid;
    @OneToMany(cascade = CascadeType.ALL, mappedBy = "userOid")
    private List<Orthopedy> orthopedyList;

    public User() {
    }
...

我无法理解： OWN连接表在哪里？为什么我有userList1和wheelchairList1？它应该识别OWN表吗？在这种情况下，我可以在这里重命名，或者我必须在一些xml文件中重命名它？

的原因

    @OneToMany(cascade = CascadeType.ALL, mappedBy = "userOid")
    private List<Orthopedy> orthopedyList;

？它应该是OneToOne ......

此外，“JSF from entities class”向导创建CRUD操作来管理用户，如何管理连接表？我需要在控制器中写一些东西吗？

你能告诉我一些可以学到这些资源的资源吗？

非常感谢你

Answer 1

创建实体时，它为所有具有主键的表创建类但不适用于拥有多对多关系的表格。它由父类管理，并作为列表进行维护。

这是我管理多对多的SubjectFaculty表的代码，其中包含教师和科目的详细信息

为学院分配科目

public void assignFacultyToSubject(String facultyUname, Integer subjectId) {
    try {
        Subject oSubject = em.find(Subject.class, subjectId);
        Faculty oFaculty = em.find(Faculty.class, facultyUname);

        College oCollege = em.find(College.class, oFaculty.getCollegeUname().getCollegeUname());

        List<Faculty> lstFaculty = oSubject.getFacultyList();
        List<Subject> lstSubject = oFaculty.getSubjectList();

        if (!lstSubject.contains(oSubject)) {
            lstFaculty.add(oFaculty);
            lstSubject.add(oSubject);

            oSubject.setFacultyList(lstFaculty);
            oFaculty.setSubjectList(lstSubject);
            em.merge(oSubject);
            em.getEntityManagerFactory().getCache().evictAll();
        } else {
            System.out.println("Entry Already Found");
        }


    } catch (Exception e) {
        System.out.println("Error :- " + e.getMessage());
    }
}

删除主题和教师详细信息表格多对多表

@Override
public void removeFacultySubject(String facultyUname, Integer subjectId) {
    try {
        Subject oSubject = em.find(Subject.class, subjectId);
        Faculty oFaculty = em.find(Faculty.class, facultyUname);

        List<Subject> lstSubject = oFaculty.getSubjectList();
        List<Faculty> lsFaculty = oSubject.getFacultyList();

        lstSubject.remove(oSubject);
        lsFaculty.remove(oFaculty);

        em.merge(oSubject);
    } catch (Exception e) {
        System.out.println("Error :- " + e.getMessage());
    }
}

来自数据库的Netbeans向导实体类，而不是映射的所有表

1 个答案: