databasebean.java

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/*
 * DataBaseBean.java
 *
 * Created on 2006年5月17日, 上午10:40
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */
package DAO;

import Bean.CartBean;
import Common.DbUtil;
import VO.CartProduct;
import VO.ProductBean;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.*;
import java.util.Enumeration;
import java.util.Hashtable;
import java.util.Vector;

/**
 *
 * @author boyingking
 */
public class DataBaseBean {

    private Connection con = null;
    public Statement stmt = null;

    private void connectTODB() {
        try {
            con = DbUtil.getConnection();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /** Creates a new instance of DataBaseBean */
    public DataBaseBean() {
    }

    public Vector selectProduct(String sql) {
        Statement stmt = null;
        ResultSet rest = null;
        Vector vec = new Vector();
        this.connectTODB();
        try {
            stmt = this.con.createStatement();
            rest = stmt.executeQuery(sql);
            while (rest.next()) {
                ProductBean temppro = new ProductBean();
                temppro.setProductId(rest.getInt("product_id"));
                temppro.setProductName(rest.getString("product_name"));
                temppro.setProductPrice(rest.getDouble("product_price"));
                temppro.setProductNum(rest.getInt("product_num"));
                temppro.setProductDescribe(rest.getString("product_describe"));
                vec.add(temppro);
            }
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
            try {
                if (rest != null) {
                    rest.close();
                }
                if (stmt != null) {
                    stmt.close();
                }
                if (this.con != null) {
                    con.close();
                }
            } catch (Exception ee) {
                ee.printStackTrace();
            }
        }
        return vec;
    }

    public void checkOut(CartBean cartbean) {
        Statement stmt = null;
        Hashtable hash = cartbean.getCartContent();
        Enumeration cartEnu = hash.elements();
        this.connectTODB();
        while (cartEnu.hasMoreElements()) {
            CartProduct cartpro = (CartProduct) cartEnu.nextElement();
            int id = cartpro.getProductId();
            int num = cartpro.getSelectedCount();
            try {
                stmt = con.createStatement();
                stmt.executeUpdate("update product set product_num=product_num-" + num + " where product_id=" + id + " and product_num>" + num);
            } catch (SQLException ex) {
                ex.printStackTrace();
            }
        }
        try {
            if (stmt != null) {
                stmt.close();
            }
            if (this.con != null) {
                con.close();
            }
        } catch (Exception ee) {
            ee.printStackTrace();
        }
    }

    public void closeDB() {
        try {
            if (stmt != null) {
                stmt.close();
            }
            con.close();
        } catch (Exception SqlE) {
            SqlE.printStackTrace();
        }
    }
}