JavaWeb项目开发案例精粹-第3章在线考试系统-003Dao层

1.

 package com.sanqing.dao;

 import java.util.List;

 import com.sanqing.po.Student;

 public interface StudentDAO {
     public Student findByStudentID(String studentID);//查询方法，根据学生ID查询
     public void updateStudent(Student student);//更新学生信息
     public List<Student> findByStudentName(String studentName);//根据学生姓名查找学生
     public List<Student> findByStudentClass(String sclass);//根据班级查找学生
 }

2.

 package com.sanqing.dao;

 import java.util.Iterator;
 import java.util.List;

 import org.hibernate.Query;
 import org.hibernate.Session;
 import org.hibernate.Transaction;

 import com.sanqing.hibernate.HibernateSessionFactory;
 import com.sanqing.po.Student;
 import com.sanqing.po.Subject;

 public class StudentDAOImpl implements StudentDAO{
     public Student findByStudentID(String studentID) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Student student = (Student) session.get(Student.class, studentID);
         HibernateSessionFactory.closeSession();//关闭Session对象
         return student;
     }

     public void updateStudent(Student student) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Transaction  transaction = null;//声明一个事务对象
         try{
             transaction = session.beginTransaction();//开启事务
             session.update(student);//更新学生信息
             transaction.commit();//提交事务
         }catch(Exception ex) {
             ex.printStackTrace();
             transaction.rollback();//事务回滚
         }
         HibernateSessionFactory.closeSession();//关闭Session对象
     }

     public List<Student> findByStudentName(String studentName) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Student as stu where stu.studentName = ?");
         query.setString(0, studentName);
         List list = query.list();                    //查询结果保存到list中
         HibernateSessionFactory.closeSession();        //关闭Session对象
         return list;
     }

     public List<Student> findByStudentClass(String sclass) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Student as stu where stu.sclass = ?");
         query.setString(0, sclass);
         List list = query.list();                    //查询结果保存到list中
         HibernateSessionFactory.closeSession();        //关闭Session对象
         return list;
     }
 }

3.

 package com.sanqing.dao;

 import java.util.List;

 import com.sanqing.po.Subject;
 import com.sanqing.util.Page;

 public interface SubjectDAO {
     public void addSubject(Subject subject);//保存方法，用来保存试题
     public Subject findSubjectByTitle(String subjectTitle);//根据试题标题查找试题
     public List<Subject> findSubjectByPage(Page page);//分页查询试题
     public int findSubjectCount();//查询试题总量
     public Subject findSubjectByID(int subjectID);//根据试题ID查找试题
     public void updateSubject(Subject subject);//更新方法，用来更新试题
     public void deleteSubject(int subjectID);//根据试题ID删除试题
     public List<Subject> likeQueryByTitle(String subjectTitle,Page page);//根据试题标题模糊查询试题
     public int findLinkQueryCount(String subjectTitle);//查询模糊记录数
     public List<Subject> randomFindSubject(int number);//随时取出记录
 }

4.

 package com.sanqing.dao;

 import java.util.List;

 import org.hibernate.Query;
 import org.hibernate.Session;
 import org.hibernate.Transaction;

 import com.sanqing.hibernate.HibernateSessionFactory;
 import com.sanqing.po.Student;
 import com.sanqing.po.Subject;
 import com.sanqing.util.Page;

 public class SubjectDAOImpl implements SubjectDAO{
     public void addSubject(Subject subject){
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Transaction  transaction = null;//声明一个事务对象
         try{
             transaction = session.beginTransaction();//开启事务
             session.save(subject);//保存试题信息
             transaction.commit();//提交事务
         }catch(Exception ex) {
             ex.printStackTrace();
             transaction.rollback();//事务回滚
         }
         HibernateSessionFactory.closeSession();//关闭Session对象
     }

     public Subject findSubjectByTitle(String subjectTitle) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Subject as sub where sub.subjectTitle = ?");
         query.setString(0, subjectTitle);
         List list = query.list();                    //查询结果保存到list中
         HibernateSessionFactory.closeSession();        //关闭Session对象
         if(list.size() == 0) {
             return null;                            //返回null
         }else {
             return (Subject) list.get(0);            //返回第一个试题
         }
     }

     public List<Subject> findSubjectByPage(Page page) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Subject");
         query.setMaxResults(page.getEveryPage());//设置查询记录数
         query.setFirstResult(page.getBeginIndex());//设置查询记录起始位置
         List list = query.list();                    //查询结果保存到list中
         HibernateSessionFactory.closeSession();//关闭Session对象
         return list;
     }

     public int findSubjectCount() {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Subject");
         List list = query.list();                    //查询结果保存到list中
         int count = list.size();
         HibernateSessionFactory.closeSession();//关闭Session对象
         return count;
     }

     public Subject findSubjectByID(int subjectID) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Subject subject = (Subject) session.get(Subject.class, subjectID);
         HibernateSessionFactory.closeSession();        //关闭Session对象
         return subject;
     }

     public void updateSubject(Subject subject) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Transaction  transaction = null;//声明一个事务对象
         try{
             transaction = session.beginTransaction();//开启事务
             session.update(subject);//更新试题信息
             transaction.commit();//提交事务
         }catch(Exception ex) {
             ex.printStackTrace();
             transaction.rollback();//事务回滚
         }
         HibernateSessionFactory.closeSession();//关闭Session对象
     }

     public void deleteSubject(int subjectID) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Subject subject = (Subject) session.get(Subject.class, subjectID);
         Transaction  transaction = null;//声明一个事务对象
         try{
             transaction = session.beginTransaction();//开启事务
             session.delete(subject);
             transaction.commit();//提交事务
         }catch(Exception ex) {
             ex.printStackTrace();
             transaction.rollback();//事务回滚
         }
         HibernateSessionFactory.closeSession();//关闭Session对象
     }

     public List<Subject> likeQueryByTitle(String subjectTitle,Page page) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Subject as sub where sub.subjectTitle like :title ");
         query.setString("title","%"+subjectTitle+"%");
         query.setMaxResults(page.getEveryPage());//设置查询记录数
         query.setFirstResult(page.getBeginIndex());//设置查询记录起始位置
         List list = query.list();                    //查询结果保存到list中
         HibernateSessionFactory.closeSession();//关闭Session对象
         return list;
     }

     public int findLinkQueryCount(String subjectTitle) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Subject as sub where sub.subjectTitle like :title ");
         query.setString("title","%"+subjectTitle+"%");
         List list = query.list();                    //查询结果保存到list中
         int count = list.size();
         HibernateSessionFactory.closeSession();//关闭Session对象
         return count;
     }

     public List<Subject> randomFindSubject(int number) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Query query = session.createQuery("from Subject as sub order by rand()");
         query.setMaxResults(number);//设置查询记录数
         List list = query.list();                    //查询结果保存到list中
         HibernateSessionFactory.closeSession();//关闭Session对象
         return list;
     }
 }

5.

 package com.sanqing.dao;

 import com.sanqing.po.Teacher;

 public interface TeacherDAO {
     public Teacher findByTeacherID(String teacherID);//查询方法，根据教师ID查询
 }

6.

 package com.sanqing.dao;

 import org.hibernate.Session;

 import com.sanqing.hibernate.HibernateSessionFactory;
 import com.sanqing.po.Teacher;

 public class TeacherDAOImpl implements TeacherDAO{
     public Teacher findByTeacherID(String teacherID) {
         Session session = HibernateSessionFactory.getSession();//获得Session对象
         Teacher teacher = (Teacher) session.get(Teacher.class, teacherID);
         HibernateSessionFactory.closeSession();//关闭Session对象
         return teacher;
     }
 }