举吊问天谁要吹
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
我们分别看看reader.java和book.java文件
Reader.java
package com.sszd.hibernate;
import java.util.HashSet;
import java.util.Set;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.FetchType;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.OneToMany;
import javax.persistence.Table;
@Entity
@Table(name="reader")
public class Reader {
@Id
@Column(name="ID")
@GeneratedValue(strategy=GenerationType.AUTO)
private int id;
@Column(name="MENO")
private String meno;
@Column(name="NAME")
private String name;
@OneToMany(mappedBy = "reader", cascade = CascadeType.ALL, fetch = FetchType.LAZY)
private Set
public Reader()
{
}
public Set getBooks() {
return books;
}
public void setBooks(Set books) {
this.books = books;
}
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getMeno() {
return meno;
}
public void setMeno(String meno) {
this.meno = meno;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
}
book.java
package com.sszd.hibernate;
import javax.persistence.CascadeType;
import javax.persistence.Column;
import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.GenerationType;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.ManyToOne;
import javax.persistence.Table;
@Entity
@Table(name="book")
public class Book {
@Id
@Column(name="ID")
@GeneratedValue(strategy=GenerationType.AUTO)
private int id;
@Column(name="TITLE")
private String title;
@ManyToOne(cascade = CascadeType.ALL, optional = false)
@JoinColumn(name="rea_id", referencedColumnName="id")//外键为sut_id，与student中的id关联
private Reader reader;
public int getId() {
return id;
}
public Reader getReader() {
return reader;
}
public void setReader(Reader reader) {
this.reader = reader;
}
public void setId(int id) {
this.id = id;
}
public String getTitle() {
return title;
}
public void setTitle(String title) {
this.title = title;
}
}
接下来是我们的本地测试用例
package com.sszd.main;
import org.hibernate.Session;
import org.hibernate.SessionFactory;
import org.hibernate.Transaction;
import org.hibernate.cfg.AnnotationConfiguration;
import com.sszd.hibernate.Book;
import com.sszd.hibernate.Reader;
public class ReaderToBooks {
private static SessionFactory sessionFactory;
public static void main(String[] args) {
sessionFactory = new AnnotationConfiguration().configure().buildSessionFactory();
Session session = sessionFactory.openSession();
Reader r = new Reader();
r.setName("Reader zhang");
Book b1 = new Book();
b1.setTitle("title1");
Book b2 = new Book();
b2.setTitle("title2");
b1.setReader(r);
b2.setReader(r);
r.getBooks().add(b1);
r.getBooks().add(b2);
Transaction trx = session.beginTransaction();
session.save(r);
trx.commit();
session.close();
}
}
我给你写一个user和role的多对多
这时user类
private?List
……省略
@ManyToMany(mappedBy?=?"userList",?fetch?=?FetchType.LAZY)
@OrderBy("id?ASC")
public?List
return?roleList;
}
这时role类
private?List
@ManyToMany(fetch?=?FetchType.LAZY)
@JoinTable(name?=?"tr_user_role",?joinColumns?=?{?@JoinColumn(name?=?"role_id")?},?inverseJoinColumns?=?{?@JoinColumn(name?=?"user_id")?})
@OrderBy("id?ASC")
public?List
return?userList;
}你进行对应的替换就行了，我设置的role是主控方
表结构就不写了，共3个表，你应该会
在student类和teacher类中，它们应该生成的都是和中间表有关的set集合吧，把它删掉，然后再各个类中配上对方的set集合.还有你生成的多对多影射关系，怎么是list而不是set。
如果你觉得答案合理，请点击采纳，举手之劳，能激励我继续为别人答题，谢谢
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