Hibernate配置（配置文件方式）

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一、双边的一对多，多对一配置（单边只要去掉一方就可以了），班级学生为例

学生类（get set 方法略）

public class Student100  implements java.io.Serializable {    // Fields         private Integer sno;     private Class100 class100;     private String name;    // Constructors    /** default constructor */    public Student100() {    }/** minimal constructor */    public Student100(Integer sno) {        this.sno = sno;    }        /** full constructor */    public Student100(Integer sno, Class100 class100, String name) {        this.sno = sno;        this.class100 = class100;        this.name = name;    }

班级类

public class Class100  implements java.io.Serializable {    // Fields         private Integer id;     private String name;     private Set students = new HashSet();    // Constructors    /** default constructor */    public Class100() {    }/** minimal constructor */    public Class100(Integer id) {        this.id = id;    }        /** full constructor */    public Class100(Integer id, String name, Set students) {        this.id = id;        this.name = name;        this.students = students;    }}

配置文件 Student100.hbm.xml

<hibernate-mapping>    <class name="com.sunny.entity100.Student100" table="student100" catalog="test100">        <id name="sno" type="java.lang.Integer">            <column name="sno" />            <generator class="identity"></generator>        </id>        <many-to-one name="class100" class="com.sunny.entity100.Class100">            <column name="class_id" /><!-- Student100表中将会生成一个外键class_id 引用Class100中的id -->        </many-to-one>        <property name="name" type="java.lang.String">            <column name="name" length="20" />        </property>    </class></hibernate-mapping>

配置文件 Class100.hbm.xml

<hibernate-mapping>    <class name="com.sunny.entity100.Class100" table="class100" catalog="test100">        <id name="id" type="java.lang.Integer">            <column name="id" />            <generator class="identity"></generator>        </id>        <property name="name" type="java.lang.String">            <column name="name" length="20" />        </property>        <set name="students" lazy="true" fetch="join" inverse="true"><!-- lazy默认为true既打开延时加载 -->            <key>                <column name="class_id" /><!-- 定义集合所对应的数据库表的外键,class_id位student表的外键 -->             </key>            <one-to-many class="com.sunny.entity100.Student100" />        </set>    </class> </hibernate-mapping>

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