跟我学Hibernate框架技术在容器外实现Hibernate框架继承映射关系第2部分

1、杨教授工作室 精心创作的优秀程序员 职业提升必读系列资料目 录1.1在容器外实现hibernate框架继承映射关系及实例（第2部分）21.1.1应用单元测试技术测试本实例的应用效果21.1.2体验hibernate中lazy技术91.1.3体验多态查询技术的应用101.1.4进一步完善本项目的实例111.1 在容器外实现hibernate框架继承映射关系及实例（第2部分）1.1.1 应用单元测试技术测试本实例的应用效果1、增加一个dao的接口derivedhibernatedaointerface包名称为er在该接口中添加下面的方法pac

2、kage er;import org.hibernate.hibernateexception;public interface derivedhibernatedaointerface public boolean dofindallpersoninfo() throws hibernateexception;2、提供对该方法的实现类derivedhibernatedaoimple包名称为com.px1987.sshwebcrm.dao.implepackage com.px1987.sshwebcrm.dao.imple;import

3、 java.util.arraylist;import java.util.list;import mons.logging.log;import mons.logging.logfactory;import org.hibernate.hibernateexception;import org.hibernate.session;import org.hibernate.transaction;import er.derivedhibernatedaointerface;import com.px1987.sshwebcrm.dao.p

4、object.abstractpersonpo;import com.px1987.sshwebcrm.dao.pobject.studentpo;import com.px1987.sshwebcrm.dao.pobject.teacherpo;import com.px1987.sshwebcrm.dao.util.hibernateutil;public class derivedhibernatedaoimple implements derivedhibernatedaointerface private static log log = logfactory.getlog(deri

5、vedhibernatedaoimple.class);public derivedhibernatedaoimple() public boolean dofindallpersoninfo() throws hibernateexception session session=null;transaction tx=null;list findresults = new arraylist();try session = hibernateutil.currentsession();tx = session.begintransaction();list allstudentinfo =

6、session.createquery("from com.px1987.sshwebcrm.dao.pobject.studentpo").list();findresults.addall(allstudentinfo);list allteacherinfo =session.createquery("from com.px1987.sshwebcrm.dao.pobject.teacherpo").list();findresults.addall(allteacherinfo); printallpersoninfo(findresults);

7、 mit();catch (hibernateexception he) log.error("在dofindallpersoninfo方法中出现了hibernateexception错误", he);throw he;finally hibernateutil.closesession();return true;private void printallpersoninfo (java.util.list allpersonlist) /利用该方法实现数据显示 java.util.iterator iterator= allpersonlist.iterator();

8、while(iterator.hasnext() abstractpersonpo oneperson=(abstractpersonpo)iterator.next(); if(oneperson instanceof studentpo) int departmentid=(studentpo)oneperson).getdepartment().getid(); string departmentname=(studentpo)oneperson).getdepartment().getdepname(); int studentid=(studentpo)oneperson).geti

9、d(); string studentname=(studentpo)oneperson).getpersonname(); int studentlevel=(studentpo)oneperson).getstudentlevel (); string studentmajor=(studentpo)oneperson).getstudentmajor(); system.out.print("departmentid="+departmentid+"t"); system.out.print("departmentname="+

10、departmentname+"t"); system.out.print("studentid="+studentid+"t"); system.out.print("studentname="+studentname+"t"); system.out.print("studentlevel="+studentlevel+"n"); system.out.print("studentmajor="+studentmajor+"

11、;n"); else int departmentid=(teacherpo)oneperson).getdepartment().getid(); string departmentname=(teacherpo)oneperson).getdepartment().getdepname(); int teacherid=(teacherpo)oneperson).getid(); string teachername=(teacherpo)oneperson).getpersonname(); string coursename=(teacherpo)oneperson).get

12、coursename(); float teachermonthsalary=(teacherpo)oneperson).getmonthsalary(); system.out.print("departmentid="+departmentid+"t"); system.out.print("departmentname="+departmentname+"t"); system.out.print("teacherid="+teacherid+"t"); system.

13、out.print("teachername="+teachername+"t"); system.out.print("teachermonthsalary="+teachermonthsalary+"n"); system.out.print("coursename="+coursename+"n"); 3、添加测试用例testderivedhibernatedaoimple包名称为com.px1987.hexample.dao.test，被测试类为derivedhibe

14、rnatedaoimple在测试用例中对该方法进行测试package com.px1987.hexample.dao.test;import junit.framework.assert;import org.junit.afterclass;import org.junit.beforeclass;import org.junit.test;import com.px1987.sshwebcrm.dao.imple.derivedhibernatedaoimple;import er.derivedhibernatedaointerfa

15、ce;public class testderivedhibernatedaoimple static derivedhibernatedaointerface onederivedhibernatedaobean=null;beforeclasspublic static void setupbeforeclass() throws exception onederivedhibernatedaobean=new derivedhibernatedaoimple();afterclasspublic static void teardownafterclass() throws except

16、ion onederivedhibernatedaobean=null;testpublic void testdofindallpersoninfo() boolean actualreturn=onederivedhibernatedaobean.dofindallpersoninfo();assert.asserttrue(actualreturn);4、执行测试用例将出现下面的结果1.1.2 体验hibernate中lazy技术如果将对department表的访问代码（也就是上面的黑体部分）除掉，然后再次执行，将发现没有对department表进行查询，因为hibernate缺省时是采

17、用 lazy加载的-只在真正需要该数据时，才加载所关联的数据。1.1.3 体验多态查询技术的应用将dao中的hql语句改变为下面的形式list allstudentinfo = session.createquery("from com.px1987.sshwebcrm.dao.pobject.studentpo").list();findresults.addall(allstudentinfo);list allteacherinfo =session.createquery("from com.px1987.sshwebcrm.dao.pobject.tea

18、cherpo").list();list allstudentinfo =session.createquery("from com.px1987.sshwebcrm.dao.pobject.abstractpersonpo").list();findresults.addall(allstudentinfo);观察执行的结果是否与前面的采用两条hql语句的效果相同。1.1.4 进一步完善本项目的实例1、在dao组件中再增加一个doinsertallpersoninfo方法以实现保存数据的功能2、修改derivedhibernatedaointerfacepack

19、age er;import org.hibernate.hibernateexception;public interface derivedhibernatedaointerface public boolean dofindallpersoninfo() throws hibernateexception;public boolean doinsertallpersoninfo() throws hibernateexception ;3、修改实现类代码示例public boolean doinsertallpersoninfo()

20、throws hibernateexception session session=null;transaction tx=null;try session = hibernateutil.currentsession();tx = session.begintransaction(); studentpo onestudent=new studentpo();onestudent.setpersonname("zhao");onestudent.setstudentlevel(4);onestudent.setstudentmajor("计算机应用")

21、; int departmentid=1;departmentpo onedepartment=(departmentpo)session.load(departmentpo.class,new integer(departmentid); onestudent.setdepartment(onedepartment); session.save(onestudent); mit();catch (hibernateexception he) log.error("在doinsertallpersoninfo方法中出现了hibernateexception错误", he);

22、throw he;finally hibernateutil.closesession();return true;4、修改测试用例package com.px1987.hexample.dao.test;import java.io.unsupportedencodingexception;import junit.framework.assert;import org.hibernate.hibernateexception;import org.junit.afterclass;import org.junit.beforeclass;import org.junit.test;import com.px1987.sshwebcrm.dao.imple.derivedhibernatedaoimple;import er.derivedhibernatedaoi