Hibernate的关系映射

Dept

package cn.et.hibernate.lesson02.relation;import java.util.HashSet;import java.util.Set;/** * Dept entity. @author MyEclipse Persistence Tools */public class Dept implements java.io.Serializable {// Fieldsprivate Short deptno;private String dname;private String loc;private Set emps = new HashSet(0);// Constructors/** default constructor */public Dept() {}/** minimal constructor */public Dept(Short deptno) {this.deptno = deptno;}/** full constructor */public Dept(Short deptno, String dname, String loc, Set emps) {this.deptno = deptno;this.dname = dname;this.loc = loc;this.emps = emps;}// Property accessorspublic Short getDeptno() {return this.deptno;}public void setDeptno(Short deptno) {this.deptno = deptno;}public String getDname() {return this.dname;}public void setDname(String dname) {this.dname = dname;}public String getLoc() {return this.loc;}public void setLoc(String loc) {this.loc = loc;}public Set getEmps() {return this.emps;}public void setEmps(Set emps) {this.emps = emps;}}

Emp

package cn.et.hibernate.lesson02.relation;import java.util.Date;/** * Emp entity. @author MyEclipse Persistence Tools */public class Emp implements java.io.Serializable {// Fieldsprivate Short empno;private Dept dept;private String ename;private String job;private Short mgr;private Date hiredate;private Double sal;private Double comm;private String sex;// Constructors/** default constructor */public Emp() {}/** minimal constructor */public Emp(Short empno) {this.empno = empno;}/** full constructor */public Emp(Short empno, Dept dept, String ename, String job, Short mgr,Date hiredate, Double sal, Double comm, String sex) {this.empno = empno;this.dept = dept;this.ename = ename;this.job = job;this.mgr = mgr;this.hiredate = hiredate;this.sal = sal;this.comm = comm;this.sex = sex;}// Property accessorspublic Short getEmpno() {return this.empno;}public void setEmpno(Short empno) {this.empno = empno;}public Dept getDept() {return this.dept;}public void setDept(Dept dept) {this.dept = dept;}public String getEname() {return this.ename;}public void setEname(String ename) {this.ename = ename;}public String getJob() {return this.job;}public void setJob(String job) {this.job = job;}public Short getMgr() {return this.mgr;}public void setMgr(Short mgr) {this.mgr = mgr;}public Date getHiredate() {return this.hiredate;}public void setHiredate(Date hiredate) {this.hiredate = hiredate;}public Double getSal() {return this.sal;}public void setSal(Double sal) {this.sal = sal;}public Double getComm() {return this.comm;}public void setComm(Double comm) {this.comm = comm;}public String getSex() {return this.sex;}public void setSex(String sex) {this.sex = sex;}}

Dept.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="cn.et.hibernate.lesson02.relation.Dept" table="DEPT" schema="SCOTT">        <id name="deptno" type="java.lang.Short">            <column name="DEPTNO" precision="3" scale="0" />            <generator class="assigned" />        </id>        <property name="dname" type="java.lang.String">            <column name="DNAME" length="14">                <comment>部门名称</comment>            </column>        </property>        <property name="loc" type="java.lang.String">            <column name="LOC" length="13">                <comment>部门所在位置</comment>            </column>        </property>                        <set name="emps" inverse="true">            <key>                <column name="DEPTNO">                    <comment>所属部门编号</comment>                </column>            </key>            <one-to-many class="cn.et.hibernate.lesson02.relation.Emp" />        </set>            </class></hibernate-mapping>

Emp.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="cn.et.hibernate.lesson02.relation.Emp" table="EMP" schema="SCOTT">        <id name="empno" type="java.lang.Short">            <column name="EMPNO" precision="4" scale="0" />            <generator class="assigned" />        </id>                        <many-to-one name="dept" class="cn.et.hibernate.lesson02.relation.Dept" fetch="select">            <column name="DEPTNO" precision="2" scale="0">                <comment>所属部门编号</comment>            </column>        </many-to-one>                        <property name="ename" type="java.lang.String">            <column name="ENAME" length="10">                <comment>员工姓名</comment>            </column>        </property>        <property name="job" type="java.lang.String">            <column name="JOB" length="9">                <comment>职位</comment>            </column>        </property>        <property name="mgr" type="java.lang.Short">            <column name="MGR" precision="4" scale="0">                <comment>领导编号</comment>            </column>        </property>        <property name="hiredate" type="java.util.Date">            <column name="HIREDATE" length="7">                <comment>雇佣日期</comment>            </column>        </property>        <property name="sal" type="java.lang.Double">            <column name="SAL" precision="7">                <comment>月薪</comment>            </column>        </property>        <property name="comm" type="java.lang.Double">            <column name="COMM" precision="7">                <comment>奖金</comment>            </column>        </property>        <property name="sex" type="java.lang.String">            <column name="SEX" length="3" />        </property>    </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>    <!-- 告诉hibernate使用的是orcle数据库 -->        <property name="dialect">org.hibernate.dialect.Oracle9Dialect</property>        <!-- 配置session Factory四要素 -->        <property name="connection.url">jdbc:oracle:thin:@localhost:1521:orcl</property>        <property name="connection.username">scott</property>        <property name="connection.password">tiger</property>        <property name="connection.driver_class">oracle.jdbc.OracleDriver</property>              <!-- 打印日志 -->    <property name="show_sql">true</property>    <!-- 扫描映射文件 -->    <mapping resource="cn/et/hibernate/lesson02/relation/Dept.hbm.xml"/>    <mapping resource="cn/et/hibernate/lesson02/relation/Emp.hbm.xml"/>    </session-factory></hibernate-configuration>

TestHibernate

package cn.et.hibernate.lesson02.relation;import org.hibernate.Session;import org.hibernate.SessionFactory;import org.hibernate.Transaction;import org.hibernate.cfg.Configuration;import org.junit.Test;public class TestHibernate {/** */@Testpublic void test(){SessionFactory sf = new Configuration().configure("/cn/et/hibernate/lesson02/relation/hibernate.cfg.xml").buildSessionFactory();Session session = sf.openSession();Dept dept = (Dept) session.get(Dept.class,Short.parseShort("10"));Emp emp = (Emp)dept.getEmps().iterator().next();System.out.println(emp.getEname());}}