hibernate多对多annotation的简单实用

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package ManyToMany;import java.util.HashSet;import java.util.Set;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.JoinTable;import javax.persistence.ManyToMany;import javax.persistence.Table;import org.hibernate.annotations.Cascade;import org.hibernate.annotations.CascadeType;@Entity@Table(name="t_student",catalog="exam")public class Student {@Id@GeneratedValue(strategy=GenerationType.IDENTITY)private Integer id;@Column(name="s_name",length=20)private String name;@ManyToMany(targetEntity=Teacher.class)//使用joinTable描述中间表,并描述表中外键与Student,Teacher的映射关系//JoininColumn描述Student与中间表的映射关系,referencedColumnName表示映射的外键,默认是主键//inverseJoinColumns描述Teacher与中间表的映射关系@JoinTable(name="s_t",joinColumns={@JoinColumn(name="c_student_id",referencedColumnName="id")},inverseJoinColumns={@JoinColumn(name="c_teacher_id",referencedColumnName="id")})@Cascade(CascadeType.SAVE_UPDATE)private Set<Teacher> teachers=new HashSet<Teacher>();public Integer getId() {return id;}public void setId(Integer id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public Set<Teacher> getTeachers() {return teachers;}public void setTeachers(Set<Teacher> teachers) {this.teachers = teachers;}}

***********************配置文件的方法

<?xml version="1.0" encoding="UTF-8"?><!DOCTYPE hibernate-mapping PUBLIC     "-//Hibernate/Hibernate Mapping DTD 3.0//EN"    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd"><hibernate-mapping><class name="ManyToMany.Student" table="t_student"><id name="id" column="id"><generator class="native"></generator></id><property name="name" column="name"/> <set name="teachers" table="t_teacher_student" cascade="save-update">         <key column="student_id"></key>         <many-to-many class="ManyToMany.Teacher" column="teacher_id" />      </set></class></hibernate-mapping>

(不建议实用)***************************

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