Hibernate集合映射之Bag

 数据库结构：

 

create table teamBag (id varchar(32),teamname varchar(32));
create table studentBag(id varchar(32),cardid varchar(32),name varchar(32),age int,description varchar(32), team_id varchar(32),cid varchar(32));

 

POJO

 

package Collection.Bag;

public class Student ...{
  private String id;
  private String name;
  private String description;
  private int age;
  private String cardid;
  private Team team;
public String getId() ...{
    return id;
}
public void setId(String id) ...{
    this.id = id;
}
public String getName() ...{
    return name;
}
public void setName(String name) ...{
    this.name = name;
}
public String getDescription() ...{
    return description;
}
public void setDescription(String description) ...{
    this.description = description;
}
public int getAge() ...{
    return age;
}
public void setAge(int age) ...{
    this.age = age;
}
public String getCardid() ...{
    return cardid;
}
public void setCardid(String cardid) ...{
    this.cardid = cardid;
}
public Team getTeam() ...{
    return team;
}
public void setTeam(Team team) ...{
    this.team = team;
}
}



package Collection.Bag;

import java.util.ArrayList;
import java.util.List;
import java.util.Map;

public class Team ...{
   private String id;
   private String teamname;
   private List students=new ArrayList();
public String getId() ...{
    return id;
}
public void setId(String id) ...{
    this.id = id;
}
public String getTeamname() ...{
    return teamname;
}
public void setTeamname(String teamname) ...{
    this.teamname = teamname;
}
public List getStudents() ...{
    return students;
}
public void setStudents(List students) ...{
    this.students = students;
}

}

 

Student.hbm.xml

 

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 
    Mapping file autogenerated by MyEclipse - Hibernate Tools
-->
<hibernate-mapping>
<class name="Collection.Bag.Student" table="studentBag" >
    <id name="id" unsaved-value="null">
      <generator class="uuid.hex"></generator>
    </id>
    <property name="cardid" type="string" column="cardid"></property>
    <property name="name" type="string" column="name"></property>
    <property name="age" type="int" column="age"></property>
    <property name="description" type="string" column="description"></property> 
    <many-to-one name="team" 
                 column="team_id"
                 class="Collection.Bag.Team" 
                 cascade="none" 
                 fetch="join">
    </many-to-one>
</class>

</hibernate-mapping>

 

Team.hbm.xml

 

<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!-- 
    Mapping file autogenerated by MyEclipse - Hibernate Tools
-->
<hibernate-mapping>
<class name="Collection.Bag.Team" table="teamBag" >
    <id name="id" unsaved-value="null">
      <generator class="uuid.hex"></generator>
    </id>
    <property name="teamname" type="string" column="teamname"></property>
      <bag name="students" table="studentBag" cascade="all,delete-orphan" >

      <key column="team_id"></key>
      <one-to-many class="Collection.Bag.Student"/>
    </bag>
</class>

</hibernate-mapping>

 

hibernate.cfg.xml

 

<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
          "-//Hibernate/Hibernate Configuration DTD 3.0//EN"
          "http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">

<!-- Generated by MyEclipse Hibernate Tools.                   -->
<hibernate-configuration>

<session-factory>
    <property name="connection.username">root</property>
    <property name="connection.url">
        jdbc:mysql://localhost:3306/schoolproject?characterEncoding=gb2312&amp;useUnicode=true
    </property>
    <property name="dialect">
        org.hibernate.dialect.MySQLDialect
    </property>
    <property name="myeclipse.connection.profile">mysql</property>
    <property name="connection.password">1234</property>
    <property name="connection.driver_class">
        com.mysql.jdbc.Driver
    </property>
    <property name="hibernate.dialect">
        org.hibernate.dialect.MySQLDialect
    </property>
    <property name="hibernate.show_sql">true</property>
    <property name