productpage.java

使用jsp+Servlet,采用MVC模式,实现了一典型小型电子商务网站的全过程.包括前台和后台的全部功能.适合于初学者学习使用.

package com.eshop.page;


import java.sql.*;
import java.util.*;

import com.eshop.util.DBManager;
import com.eshop.vo.Product;

/**
 * @author JON
 */
public class ProductPage extends PageBusiness {

	String productTable="product";
	
	
	/**
	 *构造方法
	 */
	public ProductPage()throws Exception
	{
		super();	
		v=new Vector();
	}
	/**
	 *获得所有记录数
	 */
	public int getAvailableCount(String conditions)throws Exception
	{
		DBManager dbManager=new DBManager();
		Connection conn=null;
		int ret=0;
		try
		{
				 conn=dbManager.GetConnection();
				ret=this.getAvailableCountHelper(conn,productTable,conditions);
				conn.close();
	    }
	    catch(Exception e)
	    {
	    	
	    } 
	    finally
	    {
	    	try{conn.close();}catch(Exception e2){}
	    }
	    return ret;
	}

    /**
     *查询数据库，获得要显示的信息，然后通过pageBean返回
     */
	public PageBean listData(String page,String conditions)throws Exception
	{
		DBManager dbManager=new DBManager();
		Connection conn=null;
		try
		{
			conn = dbManager.GetConnection();
            PageBean pageBean = new PageBean(this, conditions);
            int pageNum = Integer.parseInt(page);
            String sql = "SELECT top " + pageNum * pageBean.rowsPerPage + " productid,category,name,descn FROM PRODUCT where " + conditions + " order by productid desc";
            sql = "SELECT TOP " + pageBean.rowsPerPage + " * FROM (" + sql + ") a1 order by productid asc";
            String searchSql = "SELECT * FROM (SELECT productid,category,name,descn,rownumber() OVER(ORDER BY productid) AS ROW_NEXT FROM PRODUCT where " + conditions + " )AS PRODUCT_TEMP WHERE ROW_NEXT BETWEEN ? and ? ";
            PreparedStatement pstmt = conn.prepareStatement(sql);
            ResultSet rs;
            Product product;
            for(rs = pstmt.executeQuery(); rs.next(); v.add(product))
            {
                product = new Product();
                product.setProductid(rs.getString("productId"));
                product.setCategory(rs.getString("category"));
                product.setName(rs.getString("name"));
                product.setDescn(rs.getString("descn"));
            }

            rs.close();
            pstmt.close();
            conn.close();
            pageBean.curPage = pageNum;
            pageBean.data = v;
            
            return pageBean;
		}
		catch(Exception e)
		{		   
		   	e.printStackTrace();
			throw e;
			
		}
		finally
		{
				try{conn.close();}catch(Exception e2){}
		}
	}
	public Vector getResult()throws Exception
	{
		return v;
	}

}