1
我有一個電影實體和一個流派實體。如何插入一個電影與它的名稱給出的流派實體？休眠OneToMany與連接表
例如，流派表
+----+--------+
| id | name |
+----+--------+
| 1 | Action |
| 2 | Drama |
+----+--------+
電影臺
+----+----------+
| id | name |
+----+----------+
| 1 | Movie 1 |
| 2 | Movie 2 |
+----+----------+
加入表
+----+----------+-----------+
| id | movie_id | genre_id |
+----+----------+-----------+
| 1 | 1 | 1 |
| 2 | 1 | 1 |
| 3 | 1 | 2 |
+----+----------+-----------+
類型實體
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.Table;
import org.hibernate.annotations.GenericGenerator;
@Entity
@Table(name = "GENRE")
public class GenreEntity {
@Id
@Column(name = "id")
@GeneratedValue(generator="increment2")
@GenericGenerator(name="increment2", strategy = "increment")
private int id;
@Column(unique = true,name="name")
private String name;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public GenreEntity(){
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
電影實體
import java.util.ArrayList;
import java.util.Date;
import java.util.List;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinTable;
import javax.persistence.JoinColumn;
import javax.persistence.OneToMany;
import javax.persistence.Table;
import org.hibernate.annotations.GenericGenerator;
@Entity
@Table(name = "MOVIE")
public class MovieEntity {
@Id
@Column(name = "id")
@GeneratedValue(generator="increment")
@GenericGenerator(name="increment", strategy = "increment")
private int id;
@Column(name = "RELEASE_DATE")
private Date releaseDate;
@Column(name = "name")
private String name;
@Column(name = "rating")
private double rating;
@Column(name = "length")
private int length;
@Column(name = "casting")
private String casting;
@Column(name = "director")
private String director;
@Column(name = "description")
private String description;
@Column(name = "writer")
private String writer;
@OneToMany(cascade = CascadeType.ALL, orphanRemoval = true)
@JoinTable(
name = "CATEGORY",
joinColumns = @JoinColumn(name = "movie_id")
)
private List<GenreEntity> genre = new ArrayList<>();
public List<GenreEntity> getGenre() {
return genre;
}
public MovieEntity(){
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public Date getReleaseDate() {
return releaseDate;
}
public void setReleaseDate(Date releaseDate) {
this.releaseDate = releaseDate;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public double getRating() {
return rating;
}
public void setRating(double rating) {
this.rating = rating;
}
public int getLength() {
return length;
}
public void setLength(int length) {
this.length = length;
}
public String getCasting() {
return casting;
}
public void setCasting(String casting) {
this.casting = casting;
}
public String getDirector() {
return director;
}
public void setDirector(String director) {
this.director = director;
}
public String getDescription() {
return description;
}
public void setDescription(String description) {
this.description = description;
}
public String getWriter() {
return writer;
}
public void setWriter(String writer) {
this.writer = writer;
}
}
控制器
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.Configuration;
import eu.ubis.fiimdb.db.entity.GenreEntity;
import eu.ubis.fiimdb.db.entity.MovieEntity;
@WebServlet("/addmovie")
public class AddMovie extends HttpServlet {
private String message;
public void init() throws ServletException
{
// Do required initialization
message = "Hello World";
}
public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException{
// Set response content type
response.setContentType("text/html");
SessionFactory factory = new Configuration()
.configure("/META-INF/hibernate.cfg.xml")
.buildSessionFactory();
Session session=factory.getCurrentSession();
Transaction transaction = null;
try {
transaction = session.beginTransaction();
MovieEntity a = new MovieEntity();
GenreEntity b = new GenreEntity();
GenreEntity c = new GenreEntity();
b.setName("Alex");
a.setName("teeefasd");
c.setName("HGFHFG");
a.getGenre().add(b);
a.getGenre().add(c);
session.persist(a);
transaction.commit();
} catch (HibernateException e) {
transaction.rollback();
e.printStackTrace();
} finally {
session.close();
}
}
}
當我添加一個電影，我想在HTML中選擇標籤和休眠添加流派連接表中不插入流派表和連接表。
如何識別這些類型，讓hibernate不會再插入它們？
最後，我想要轉到一個頁面，輸入一個電影名稱並選擇適用於該電影並提交的多個流派。