Hibernate多对多双向关联(annotation/xml)

1.annotatiton

实体类

Student.java

package com.test.hiberenate.model;

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;

@Entity
public class Student {
	private int id;
	private String name;
	private Set<Teacher> teachers = new HashSet<Teacher>();

	@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 = "student_id"), inverseJoinColumns = @JoinColumn(name = "teacher_id"))
	public Set<Teacher> getTeachers() {
		return teachers;
	}

	public void setTeachers(Set<Teacher> teachers) {
		this.teachers = teachers;
	}

}

 

Teacher.java

package com.test.hiberenate.model;

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 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(mappedBy="teachers")
	public Set<Student> getStudents() {
		return students;
	}

	public void setStudents(Set<Student> students) {
		this.students = students;
	}

}

 

2.xml

Student.hbm.xml

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

<hibernate-mapping package="com.test.hiberenate.model">
	<class name="Student">
		<id name="id">
			<generator class="native"></generator>
		</id>
		<property name="name" />
		<set name="teachers" table="t_s">
			<key column="student_id"></key>
			<many-to-many class="Teacher" column="teacher_id"></many-to-many>
		</set>
	</class>
</hibernate-mapping>

 

Teacher.hbm.xml

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

<hibernate-mapping package="com.test.hiberenate.model">
	<class name="Teacher">
		<id name="id">
			<generator class="native"></generator>
		</id>
		<property name="name" />
		<set name="students" table="t_s">
			<key column="teacher_id"></key>
			<many-to-many class="Student" column="student_id"></many-to-many>
		</set>
	</class>
</hibernate-mapping>