示例數(shù)據(jù)表：team(班級)、certificate(身份證)、student(學(xué)生)

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 Persistence Tools
-->
<hibernate-mapping>
    <class name="edu.dgut.ke.model.Team" table="TEAM"  lazy ="true"  ><!-- 多對一的延遲加載設(shè)置 -->
        <id name="id" type="java.lang.String">
            <column name="ID" length="32" />
            <generator class="uuid.hex" />
        </id>
        <property name="teamname" type="java.lang.String">
            <column name="TEAMNAME" length="32" not-null="true" unique="true" />
        </property>
        <set name="students" inverse="true" cascade="all" lazy="true" >  <!-- 一對多的延遲加載設(shè)置 -->
            <key>
                <column name="TEAMID" length="32" not-null="true" />
            </key>
            <one-to-many class="edu.dgut.ke.model.Student" />
        </set>
    </class>
</hibernate-mapping>

Certificate.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 Persistence Tools
-->
<hibernate-mapping>
    <class name="edu.dgut.ke.model.Certificate" table="CERTIFICATE" lazy="true"  ><!-- 一對一的延遲加載設(shè)置 -->

        <id name="id" type="java.lang.String">
            <column name="ID" length="32" />
            <generator class="uuid">
           
            </generator>
        </id>
        <property name="describe" type="java.lang.String">
            <column name="`DESCRIBE`" length="50" not-null="true" />
        </property>
        <one-to-one name="student"
         class="edu.dgut.ke.model.Student"
         constrained="true"  ><!-- 一對一的延遲加載設(shè)置 -->

        </one-to-one>
    </class>
</hibernate-mapping>

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 Persistence Tools
-->
<hibernate-mapping>
    <class name="edu.dgut.ke.model.Student" table="STUDENT" lazy="true"  >
        <id name="id" type="java.lang.String">
            <column name="ID" length="32" />
            <generator class="uuid.hex" />
        </id>
        <many-to-one name="certificate"
         class="edu.dgut.ke.model.Certificate"
         unique="true"
         column="cardId"
         cascade="all"
         >
        </many-to-one>
        <many-to-one name="team" class="edu.dgut.ke.model.Team">
            <column name="TEAMID" length="32" not-null="true" />
        </many-to-one>
        <property name="studentname" type="java.lang.String">
            <column name="STUDENTNAME" length="16" not-null="true" unique="true" />
        </property>
    </class>
</hibernate-mapping>
注意：對one-to-one 關(guān)系進行延遲加載和其他關(guān)系相比稍微有些不同。many-to-one 的延遲加載是在配置文件的class 標簽
上設(shè)置 lazy="true" ，one-to-many 和 many-to-many 的延遲加載是在 set 標簽中設(shè)置lazy="true"。而one-to-one 不只要在 classs
標簽設(shè)置 lazy="true"，而且要在one-to-one 標簽中設(shè)置constrained="true" 。
如果不設(shè)置constrained="true"，則一對一查詢使用默認的預(yù)先抓取策略(fetch="join")。