1 package com.qcf.pox; 2  3 import java.util.HashSet; 4 import java.util.Set; 5  6 import javax.persistence.Entity; 7 import javax.persistence.GeneratedValue; 8 import javax.persistence.GenerationType; 9 import javax.persistence.Id;10 import javax.persistence.ManyToMany;11 12 @Entity13 public class Course {14     @Id15     @GeneratedValue(strategy=GenerationType.AUTO)16     private int id;17     private String name;18     @ManyToMany(mappedBy="courses")19     private Set<Student2> student2s=new HashSet<Student2>();20     public int getId() {21         return id;22     }23     public void setId(int id) {24         this.id = id;25     }26     public String getName() {27         return name;28     }29     public void setName(String name) {30         this.name = name;31     }32     public Set<Student2> getStudent2s() {33         return student2s;34     }35     public void setStudent2s(Set<Student2> student2s) {36         this.student2s = student2s;37     }38     public Course(int id, String name, Set<Student2> student2s) {39         super();40         this.id = id;41         this.name = name;42         this.student2s = student2s;43     }44     public Course() {45         super();46     }47     48 }

 1 package com.qcf.pox; 2  3 import java.util.HashSet; 4 import java.util.Set; 5  6 import javax.persistence.CascadeType; 7 import javax.persistence.Entity; 8 import javax.persistence.GeneratedValue; 9 import javax.persistence.GenerationType;10 import javax.persistence.Id;11 import javax.persistence.ManyToMany;12 13 @Entity14 public class Student2 {15     @Id16     @GeneratedValue(strategy=GenerationType.AUTO)17     private int id;18     private String name;19     @ManyToMany(cascade=CascadeType.ALL)20     private Set<Course> courses=new HashSet<Course>();21     public int getId() {22         return id;23     }24     public void setId(int id) {25         this.id = id;26     }27     public String getName() {28         return name;29     }30     public void setName(String name) {31         this.name = name;32     }33     public Set<Course> getCourses() {34         return courses;35     }36     public void addCourses(Course courses) {37         this.courses.add(courses);38     }39     public Student2(int id, String name, Set<Course> courses) {40         super();41         this.id = id;42         this.name = name;43         this.courses = courses;44     }45     public Student2() {46         super();47     }48     49 }

1         <mapping class="com.qcf.pox.Student2"/>2         <mapping class="com.qcf.pox.Course"/>

 1 package com.qcf.test; 2  3 import org.hibernate.Session; 4 import org.hibernate.SessionFactory; 5 import org.hibernate.Transaction; 6 import org.hibernate.cfg.AnnotationConfiguration; 7 import org.hibernate.cfg.Configuration; 8  9 import com.qcf.pox.Course;10 import com.qcf.pox.Student2;11 12 public class TestManyToMany {13     public static void main(String[] args) {14         Configuration configuration=new AnnotationConfiguration().configure();15         SessionFactory factory=configuration.buildSessionFactory();16         Session session=factory.openSession();17         Transaction transaction=session.beginTransaction();18         19         //创建两个课程20         Course course=new Course();21         course.setName("java");22         Course course2=new Course();23         course2.setName("C#");24         25         //创建两个学生26         Student2 student=new Student2();27         student.setName("zhangsan");28         Student2 student2=new Student2();29         student2.setName("lisi");30         31         student.addCourses(course);32         student.addCourses(course2);33         34         student2.addCourses(course);35         student2.addCourses(course2);36         37         session.save(student);38         session.save(student2);39         40         transaction.commit();41         session.close();42         43     }44 45 }