coursebeanbo.java

课程管理系统

//这个类处理course的添加修改分页等等操作；
package cn.rludrea.model;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;

public class CourseBeanBO {
	//定义一些变量[]；
	private ResultSet rs=null;
	private Connection ct=null;
	private PreparedStatement ps=null;
	/**
	 * 返回总共有多少页；
	 * @author rludrea
	 * @param pageSize
	 * @return int :返回一个总共有多少页；
	 */
	public int getPageCount(int pageSize)
	{
		int pageCount=0;
		int rowCount=0;
		try{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select count(*) from course");
			rs=ps.executeQuery();
			if(rs.next())
			{
				rowCount=rs.getInt(1);
			}
			if(rowCount%pageSize==0)
			{
				pageCount=rowCount/pageSize;
			}
			else
			{
				pageCount=rowCount/pageSize+1;
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}finally
		{
			new close().Close();
		}
		
		return pageCount; 
	}
	/**
	 * 分页显示选课的简单内容；
	 * @author rludrea
	 * @param pageSize (int) 
	 * @param pageNow (int)
	 * @return ArrayList 返回一个数组集；
	 */
	public ArrayList getCourseByPage(int pageSize,int pageNow)
	{
		ArrayList al=new ArrayList();
		try
		{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select top "+pageSize+" * from course where courseId not in(select top "+(pageNow-1)*pageSize+" courseId from course)");
			rs=ps.executeQuery();
			while(rs.next())
			{
				CourseBean cb=new CourseBean();
				cb.setCourseId(rs.getInt(1));
				cb.setCourseName(rs.getString(2));
				cb.setTeacherName(rs.getString(3));
				cb.setSecTeaName(rs.getString(4));
				cb.setCourseIntro(rs.getString(5));
				cb.setImages(rs.getString(6));
				
				al.add(cb);
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}finally
		{
			new close().Close();
		}
		return al;
	}
	public ArrayList getCourseLikeByPage(int pageSize,int pageNow,String courseName)
	{
		ArrayList al=new ArrayList();
		try
		{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select top "+pageSize+" * from course where courseName like '%"+courseName+"%' and courseId not in(select top "+(pageNow-1)*pageSize+" courseId from course)");
			rs=ps.executeQuery();
			while(rs.next())
			{
				CourseBean cb=new CourseBean();
				cb.setCourseId(rs.getInt(1));
				cb.setCourseName(rs.getString(2));
				cb.setTeacherName(rs.getString(3));
				cb.setSecTeaName(rs.getString(4));
				cb.setCourseIntro(rs.getString(5));
				cb.setImages(rs.getString(6));
				
				al.add(cb);
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			new close().Close();
		}
		return al ;
	}
	/**
	 * 根据传过来courseId取得一个courseBean;
	 * @author rludrea
	 * @param courseId (String)
	 * @return 返回一个courseBean
	 */
	public CourseBean getCourseBean(String courseId)
	{
		CourseBean cb=new CourseBean();
		try
		{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select top 1 * from course where courseId =?");
			ps.setString(1, courseId);
			rs=ps.executeQuery();
			if(rs.next())
			{
				cb.setCourseId(rs.getInt(1));
				cb.setCourseName(rs.getString(2));
				cb.setTeacherName(rs.getString(3));
				cb.setSecTeaName(rs.getString(4));
				cb.setCourseIntro(rs.getString(5));
				cb.setImages(rs.getString(6));
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			new close().Close();
		}
		return cb;
	}
	/**
	 * 这是一个模糊查询的方法。根据选课名查找所有符合的数据集；
	 * @param courseName
	 * @return al(ArrayList)
	 */
	public ArrayList getCourseBeanByCourseName(int pageSize, String courseName)
	{		
		ArrayList al=new ArrayList();
		try
		{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select top "+pageSize+" * from course where courseName like '%"+courseName+"%' order by len(courseName) asc");
			rs=ps.executeQuery();
			while(rs.next())
			{
				CourseBean cb=new CourseBean();
				cb.setCourseId(rs.getInt(1));
				cb.setCourseName(rs.getString(2));
				cb.setTeacherName(rs.getString(3));
				cb.setSecTeaName(rs.getString(4));
				cb.setCourseIntro(rs.getString(5));
				cb.setImages(rs.getString(6));
				
				al.add(cb);
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			new close().Close();
		}
		return al;
	}
	/**
	 * 这是一个获得模糊查询的共页数；
	 * @param pageSize 每页显示的记录；
	 * @param courseName 
	 * @return pageCount (int)返回一个整型的总页数的数据；
	 */
	public int getLikePageCount(int pageSize,String courseName)
	{
		int pageCount=0;
		int rowCount=0;
		try
		{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select count (*) from course where courseName like '%"+courseName+"%'");
			rs=ps.executeQuery();
			if(rs.next())
			{
				rowCount=rs.getInt(1);
			}
			if(rowCount%pageSize==0)
			{
				pageCount=rowCount/pageSize;
			}
			else
			{
				pageCount=rowCount/pageSize+1;
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			new close().Close();
		}
		return pageCount;
	}
	/**
	 * 这个类是用来更新选课的~~用户可以修改自己的选课；
	 * @author rludrea
	 * @param courseId
	 * @param stuName
	 * @return boolean 返回一个布尔值表示是否更新成功；
	 */
	public boolean updateStuCourse(String courseId,String stuName)
	{
		boolean b=false;
		try
		{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("update student set courseId=? where stuName=?");
			ps.setString(1, courseId);
			ps.setString(2, stuName);
			int index=ps.executeUpdate();
			if(index==1)
			{
				b=true;
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}
		finally
		{
			new close().Close();
		}
		return b;
	}
	/**
	 * 这是一个获得用户名来取得选择的课程id
	 * @author rludrea
	 * @param stuName
	 * @return String 返回一个选课的String；
	 */
	public String getCourseIdBystuName(String stuName)
	{
		String courseId=null;
		try{
			ct=new ConnDB().getConn();
			ps=ct.prepareStatement("select top 1 courseId from student where stuName=?");
			ps.setString(1, stuName);
			rs=ps.executeQuery();
			if(rs.next())
			{
				courseId=rs.getString(1);
			}
		}catch(Exception e)
		{
			e.printStackTrace();
		}finally
		{
			new close().Close();
		}
		return courseId;
	}
}