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;
    }
}