hibernate实体N对N映射实例（1）

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hibernate配置文件

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

<hibernate-configuration>
<session-factory>
<property name="show_sql">true</property>
<property name="connection.isolation">2</property>
<property name="myeclipse.connection.profile">mysqlyuan</property>
<property name="connection.url">jdbc:mysql://127.0.0.1:3306/test</property>
<property name="connection.username">root</property>
<property name="connection.password">1234</property>
<property name="hbm2ddl.auto">create</property>
<property name="connection.driver_class">
   com.mysql.jdbc.Driver
</property>
<property name="dialect">
   org.hibernate.dialect.MySQLDialect
</property>
<mapping resource="com/tarena/enrollment/biz/entity/Student.hbm.xml" />
<mapping resource="com/tarena/enrollment/biz/entity/Course.hbm.xml" />
</session-factory>
</hibernate-configuration>

Course.hbm.xml关系映射文件

<?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 package="com.tarena.enrollment.biz.entity">
<class name="Course" table="t_course_many2many" >
<id name="oid"
     column="OID">
   <generator class="native"/>
</id>

<property name="cid"
         column="CID"
         unique="true"
         not-null="true"/>
<property name="name"
         column="NAME"
         not-null="true" />
   <set name="stus" table="t_enrollment"
          cascade="save-update">
    <key column="CFID"/>
    <many-to-many class="Student"
              column="SFID"/>
   </set>
</class>
</hibernate-mapping>


Student.hbm.xml关系映射文件

<?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 package="com.tarena.enrollment.biz.entity">
<class name="Student" table="s_student_man2many">
   <id name="oid" column="OID">
     <generator class="native"/>
   </id>
   <property name="sid"
          column="STUDENTID"
          unique="true"
          not-null="true"/>
   <property name="name"
          column="STUDENTNAME"
          not-null="true"/>
   <set name="cours" table="t_enrollment"
              cascade="save-update"
              inverse="true">
     <key column="SFID"/>
     <many-to-many class="Course"
               column="CFID"/>
   </set> 
  
</class>
</hibernate-mapping>

实体类Course.java

package com.tarena.enrollment.biz.entity;

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

public class Course {
private Long oid;
private String cid;
private String name;

private Set stus=new HashSet();

public Course(){}

public Course(String cid, String name) {
   super();
   this.cid = cid;
   this.name = name;

}

public Course(String cid, String name, Set stus) {
   super();
   this.cid = cid;
   this.name = name;
   this.stus = stus;
}

public Long getOid() {
   return oid;
}

public void setOid(Long oid) {
   this.oid = oid;
}

public String getCid() {
   return cid;
}

public void setCid(String cid) {
   this.cid = cid;
}

public String getName() {
   return name;
}

public void setName(String name) {
   this.name = name;
}

public Set getStus() {
   return stus;
}

public void setStus(Set stus) {
   this.stus = stus;
}
@Override
public int hashCode() {
   final int prime = 31;
   int result = 1;
   result = prime * result + ((cid == null) ? 0 : cid.hashCode());
   return result;
}
@Override
public boolean equals(Object obj) {
   if (this == obj)
    return true;
   if (obj == null)
    return false;
   if (getClass() != obj.getClass())
    return false;
   final Course other = (Course) obj;
   if (cid == null) {
    if (other.cid != null)
     return false;
   } else if (!cid.equals(other.cid))
    return false;
   return true;
}

}


Student.java实体类

package com.tarena.enrollment.biz.entity;

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

public class Student {
private Long oid;
private String sid;
private String name;

private Set cours=new HashSet();

public Student(){}

public Student(String sid, String name) {
   super();
   this.sid = sid;
   this.name = name;
}

public Student(String sid, String name, Set cours) {
   super();
   this.sid = sid;
   this.name = name;
   this.cours = cours;
}

public void registerCour(Course cour){
   cours.add(cour);
   cour.getStus().add(this);
}

public Long getOid() {
   return oid;
}

public void setOid(Long oid) {
   this.oid = oid;
}

public String getSid() {
   return sid;
}

public void setSid(String sid) {
   this.sid = sid;
}

public String getName() {
   return name;
}

public void setName(String name) {
   this.name = name;
}

public Set getCours() {
   return cours;
}

public void setCours(Set cours) {
   this.cours = cours;
}

@Override
public int hashCode() {
   final int prime = 31;
   int result = 1;
   result = prime * result + ((sid == null) ? 0 : sid.hashCode());
   return result;
}

@Override
public boolean equals(Object obj) {
   if (this == obj)
    return true;
   if (obj == null)
    return false;
   if (getClass() != obj.getClass())
    return false;
   final Student other = (Student) obj;
   if (sid == null) {
    if (other.sid != null)
     return false;
   } else if (!sid.equals(other.sid))
    return false;
   return true;
}

}