J2EE应用持久化和Hibernate.ppt
第六讲 数据库连接和Hibernate(三)Hibernate开发实例内容安排nMyEclipse 开发开发Hibernate过程过程n三种映射关系实例MyEclipse 开发Hibernate过程n创建Web/JAVA 工程n增加Hibernate功能qMyEclipse-Add Hibernate Capabilitiesn确定数据库连接细节q需要实现创建DB DriverqWindow-Show View-Other-DB BrowserHibernate反向工程生成映射文件和类文件nAbstractAddr.javanAddr.javanAddrDAO.java一对一关联Userinfo表结构ncreate table USERINFOn(n USERID VARCHAR2(20)not null,n USERNAME VARCHAR2(20),n AGE VARCHAR2(20),n ADDRID VARCHAR2(20),n PRIMARY KEY (USERID),n CONSTRAINT addrid FOREIGN KEY(ADDRID)REFERENCES addr(ADDRID)n)Addr表结构ncreate table ADDRn(n ADDRID VARCHAR2(20)not null,n LOCATION VARCHAR2(20),n POSTCODE VARCHAR2(20),n PRIMARY KEY (ADDRID)n)Addr POJOnpublic class Addr implements java.io.Serializable n/Fieldsnprivate String addrid;nprivate String location;nprivate String postcode;nAddr映射描述nn n n n n n n n n n nUserinfo POJOnpublic class Userinfo implements java.io.Serializable n/Fieldsnprivate String userid;nprivate Addr addr;nprivate String username;nprivate String age;nUserinfo映射文件描述 关联查询nSession session=HibernateSessionFactory.getSession();nUserinfo u=(Userinfo)session.load(Userinfo.class,1001);nSystem.out.println(u.getUsername();nSystem.out.println(u.getAddr().getLocation();nHibernateSessionFactory.closeSession();关联保存nUserinfo u=new Userinfo();nu.setUserid(1002);nu.setUsername(JONES);nu.setAge(26);n/级联保存addr的信息,而不再需要单独save方法,hibernate会自动save addr的信息nAddr addr=new Addr();naddr.setAddrid(SHANGHAI002);naddr.setLocation(BAOSHANLU);naddr.setPostcode(200852);nu.setAddr(addr);nTransaction t=session.beginTransaction();nsession.save(u);mit();多对一关联多对一表结构create table EMPLOYEE(EMPID VARCHAR2(50)not null,ENAME VARCHAR2(20),SAL VARCHAR2(20),JOB VARCHAR2(20),DEPTID VARCHAR2(20);create table DEPARTMENT(DEPTID VARCHAR2(50)not null,DNAME VARCHAR2(20),LOCATION VARCHAR2(20);或:Department.javaprivate String deptid;private String dname;private String location;private Set emps;public Set getEmps()return emps;public void setEmps(Set emps)this.emps=emps;.nnn或nn nEmployee.javaprivate String empid;private String ename;private String sal;private String job;private Department dept;public Department getDept()return dept;public void setDept(Department dept)this.dept=dept;级联保存Session s=HibernateSessionFactory.getSession();Department d=new Department();d.setDeptid(1001);d.setDname(R&D);d.setLocation(NEW YORK);Set emps=new HashSet();Employee e1=new Employee(7001,zhangshan,5000,CLERK);Employee e2=new Employee(7002,lishi,6000,SALESMAN);Employee e3=new Employee(7003,wangwu,7000,MANAGER);emps.add(e1);emps.add(e2);emps.add(e3);d.setEmps(emps);Transaction t=s.beginTransaction();s.save(d);mit();HibernateSessionFactory.closeSession();级联删除Session s=HibernateSessionFactory.getSession();Department d=new Department();d.setDeptid(1001);Set emps=new HashSet();Employee e1=new Employee(7001);Employee e2=new Employee(7002);Employee e3=new Employee(7003);emps.add(e1);emps.add(e2);emps.add(e3);d.setEmps(emps);Transaction t=s.beginTransaction();s.delete(d);mit();HibernateSessionFactory.closeSession();级联查询Session s=HibernateSessionFactory.getSession();Query q=s.createQuery(select e from Employee e where e.empid=7001);List list=q.list();for(int i=0;ilist.size();i+)Employee e=(Employee)list.get(i);Department d=e.getDept();System.out.println(d.getDname();HibernateSessionFactory.closeSession();多对多关联多对多表结构create table COURSE(COURID VARCHAR2(50)not null primary key,COURNAME VARCHAR2(20);create table STUDENT(STUID VARCHAR2(50)not null primary key,STUNAME VARCHAR2(20);create table STUCOUR(STUID VARCHAR2(50)not null,COURID VARCHAR2(50)not null);Student.javanprivate String stuid;nprivate String stuname;nprivate Set cours;Course.javanprivate String courid;nprivate String courname;nprivate Set stus;Stucour.javanprivate StucourId id;主键类StucourIdnprivate String stuid;nprivate String courid;Student.xml级联保存Session s=HibernateSessionFactory.getSession();Student stu=new Student();stu.setStuid(1002);stu.setStuname(zhangshan);Set cours=new HashSet();Course c1=new Course(9001,English);Course c2=new Course(9002,phylisc);cours.add(c1);cours.add(c2);stu.setCours(cours);Transaction t=s.beginTransaction();s.save(stu);mit();HibernateSessionFactory.closeSession();级联查询Session s=HibernateSessionFactory.getSession();Student stu=new Student();stu=(Student)s.get(Student.class,1001);System.out.println(stu.getStuid()+:+stu.getStuname();Set cours=stu.getCours();Iterator it=cours.iterator();while(it.hasNext()Course c=(Course)it.next();System.out.println(c.getCourname();HibernateSessionFactory.closeSession();删除学生Session s=HibernateSessionFactory.getSession();Student stu=new Student();stu.setStuid(1001);Transaction t=s.beginTransaction();s.delete(stu);mit();HibernateSessionFactory.closeSession();自动删除关联表中的信息删除学生及关联课程在删除学生信息的同时,删除关联课程信息Session s=HibernateSessionFactory.getSession();Student stu=new Student();stu.setStuid(1001);Set cours=new HashSet();Course c1=new Course(9001);Course c2=new Course(9002);cours.add(c1);cours.add(c2);stu.setCours(cours);Transaction t=s.beginTransaction();s.delete(stu);mit();HibernateSessionFactory.closeSession();删除学生及关联课程删除学生信息,同时查询该学生对应的所有课程信息,一并删除Session s=HibernateSessionFactory.getSession();Student stu=new Student();stu.setStuid(1001);Query q=s.createQuery(select c from Course c,Stucour sc +where c.courid=sc.id.courid and sc.id.stuid=1001);List list=q.list();Set cours=new HashSet();for(int i=0;ilist.size();i+)cours.add(list.get(i);stu.setCours(cours);Transaction t=s.beginTransaction();s.delete(stu);mit();HibernateSessionFactory.closeSession();