hibernate 多对多双向关联

package com.bjsxt.hibernate;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.ManyToMany;

@Entity
public class Student {
    private int id;
    private String name;
    private Set<Teacher> teachers = new HashSet<Teacher>();
    @ManyToMany(mappedBy="students")
    public Set<Teacher> getTeachers() {
        return teachers;
    }
    public void setTeachers(Set<Teacher> teachers) {
        this.teachers = teachers;
    }
    @Id
    @GeneratedValue
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

package com.bjsxt.hibernate;

import java.util.HashSet;
import java.util.Set;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.JoinColumn;
import javax.persistence.JoinTable;
import javax.persistence.ManyToMany;
import javax.persistence.OneToMany;
import javax.persistence.Table;

@Entity
public class Teacher {
    private int id;
    private String name;
    private Set<Student> students = new HashSet<Student>();
    @Id
    @GeneratedValue
    public int getId() {
        return id;
    }
    public void setId(int id) {
        this.id = id;
    }
    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
    @ManyToMany
    @JoinTable(name="t_s",
        joinColumns={@JoinColumn(name="teacher_id")},
        inverseJoinColumns={@JoinColumn(name="student_id")}
        )
    public Set<Student> getStudents() {
        return students;
    }
    public void setStudents(Set<Student> students) {
        this.students = students;
    }
}

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
    <class name="com.bjsxt.hibernate.Student">
        <id name="id">
            <generator class="native"></generator>
        </id>

        <property name="name"></property>
        <set name="teachers" table="t_s">
            <key column="student_id"></key>
            <many-to-many class="com.bjsxt.hibernate.Teacher" column="teacher_id"/>
        </set>
    </class>

</hibernate-mapping>

<?xml version="1.0"?>
<!DOCTYPE hibernate-mapping PUBLIC
"-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">

<hibernate-mapping>
    <class name="com.bjsxt.hibernate.Teacher">
        <id name="id">
            <generator class="native"></generator>
        </id>

        <property name="name"></property>
        <set name="students" table="t_s">
            <key column="teacher_id"></key>
            <many-to-many class="com.bjsxt.hibernate.Student" column="student_id"/>
        </set>
    </class>

</hibernate-mapping>

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hibernate 多对多双向关联

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