studentdao.java

采用STRUTS+HIBERNATE做的一个学生成绩管理系统.用的ORACLE9I数据库.

package org.yangyang.dao;

import java.util.Date;
import java.util.List;

import org.hibernate.Criteria;
import org.hibernate.Session;
import org.hibernate.Transaction;
import org.hibernate.criterion.Expression;
import org.hibernate.criterion.Order;
import org.yangyang.bean.Course;
import org.yangyang.bean.Student;
import org.yangyang.db.DbCon;

public class StudentDao extends MainDao {
	
    public StudentDao(){
        super.sio = new DbCon().getSession();
    }
    
	/** 
	 * Method showStudent 显示学生
	 * @param pagenum    开始的页数
	 * @param count      显示的个数
	 * @return List<Student> 
	 */
    public List<Student> showStudent(int pagenum,int count){
    	List<Student> resultList;
    	//起始个数
    	int startnum = (pagenum - 1) * count;
    	//注入查找的表名
    	Criteria criteria = sio.createCriteria(Student.class);
    	//判断时候删除
    	criteria.add(Expression.isNull("deldate"));
    	//设置开始的个数
    	criteria.setFirstResult(startnum);
    	//设置最大查找的个数
    	criteria.setMaxResults(count);
    	//按编号降序排列
    	criteria.addOrder(Order.desc("id"));
    	//进行查找
    	resultList = criteria.list();
    	return resultList;
    }
    
	/** 
	 * Method getSudentbyId 通过编号得到学生
	 * @param id           学生编号
	 */
    public Student getSudentbyId(String id){
    	//注入查找的表名
    	Criteria criteria = sio.createCriteria(Student.class);
    	//判断时候删除
    	criteria.add(Expression.eq("id",id));
    	//进行查找
    	Student stu = (Student) criteria.list().get(0);
        return stu;
    	
    }
    
	@Override
	public int getPage(int count,Object obj) {
    	//总结果
    	int totalNum = 0;
    	//页面数
    	int pageNum = 0;
    	//注入查找的表名
    	Criteria criteria = sio.createCriteria(Student.class);
    	//判断是否删除
    	criteria.add(Expression.isNull("deldate"));
        //查找总结果数
        totalNum = criteria.list().size();
        if(totalNum != 0){
        	//计算页面数
        	if(totalNum % count == 0){        		
        		pageNum = totalNum / count;
        	}else{
        		pageNum = totalNum / count + 1;
        	}
        }else{
        	pageNum = -1;
        }
        return pageNum;
	}
	
	@Override
    public void del(String id,String tablename){
    	//开启事务
        trans = sio.beginTransaction();
        //查找要删除的学生
        String sql = "from org.yangyang.bean." + tablename + " tab where tab.id=" + id;
        Student stu = (Student) sio.createQuery(sql).list().get(0);
        //输入删除时间
        stu.setDeldate(new Date());
        //进行删除
        sio.saveOrUpdate(stu);
        //提交事务
        trans.commit();
    }
	
	/** 
	 * Method getSudentbyId 得到所有学生信息
	 * 	 * @return List<Course> 
	 */
    public List<Student> getAll(){
    	List<Student> result;
    	//注入查找的表名
    	Criteria criteria = sio.createCriteria(Student.class);
    	//判断是否删除
    	criteria.add(Expression.isNull("deldate"));
    	//进行查找
    	result =  criteria.list();
        return result;
    }
}