JavaWeb基础+oracle实现简单简单分页商品浏览与加入购物车系统

1.首先建立项目，大概目录如下图

绪论：也是一个小作业，测试过没有什么bug，数据库用的tomcat连接池，我也是初学者，分享出来对java的初学者或许会有小帮助，

1.1商品的po层里面就是和数据库表字段对应的数据的get和set方法和构造方法。

2.首先是商品浏览模块的IGoodsDao接口

package cn.hpe.dao;

import java.util.List;

import cn.hpe.po.GoodsInfo;

public interface IGoodsDao {

/**
* 分页显示商品信息的栏目 pageSize=3;
*
* @return
*/
public List<GoodsInfo> getGoodsList(int currentPages, int pageSizes)
throws Exception;

/**
* 获取总页数
*/
public int getAllPage() throws Exception;

/**
* 查询所有商品的信息； return list;
*/
public List<GoodsInfo> getAllGoodsList(String id) throws Exception;

}

2.1是商品浏览界面的实现部分

package cn.hpe.dao.impl;

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

import cn.hpe.dao.BaseDao;
import cn.hpe.dao.IGoodsDao;
import cn.hpe.po.GoodsInfo;

public class GoodsDaoImpl implements IGoodsDao {

/**
* 分页显示商品信息的栏目 pageSize=3;
*
* @return
*/
@Override
public List<GoodsInfo> getGoodsList(int currentPages, int pageSizes)
throws Exception {
List<GoodsInfo> list = new ArrayList<GoodsInfo>();
try {
int currentPage = currentPages;
int pageSize = pageSizes;
int xy = currentPage * pageSize;
int dy = (currentPage - 1) * pageSize;
Connection conn = BaseDao.getConn();
String sql = "select * from (select t.*,rownum r from TB_GOODS t where rownum<="
+ xy + ")where r>" + dy + "";

PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery();
while (rs.next()) {
GoodsInfo gi = new GoodsInfo();
gi.setId(rs.getString("ID"));
gi.setName(rs.getString("NAME"));
gi.setPrice(rs.getDouble("PRICE"));
gi.setCompany(rs.getString("COMPANY"));
gi.setLeaveDate(rs.getString("LEAVE_DATE"));
gi.setDescription(rs.getString("DESCRIPTION"));
list.add(gi);
}
rs.close();
ps.close();
conn.close();

} catch (Exception ex) {
ex.printStackTrace();
throw new Exception();
}

return list;
}

/**
* 获取总页数
*/
@Override
public int getAllPage() throws Exception {
int allPage = 0;
try {
Connection conn = BaseDao.getConn();
String sql = "Select count(*) allPage from TB_GOODS";
PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery();
while (rs.next()) {
allPage = rs.getInt("allPage");
}

rs.close();
ps.close();
conn.close();

} catch (Exception ex) {
ex.printStackTrace();
throw new Exception();
}
return allPage;
}

/**
* 查询所有商品的信息； return list;
*/
@Override
public List<GoodsInfo> getAllGoodsList(String id) throws Exception {
List<GoodsInfo> list = new ArrayList<GoodsInfo>();
try {

Connection conn = BaseDao.getConn();
String sql = "select * from TB_GOODS where id=?";

PreparedStatement ps = conn.prepareStatement(sql);
ps.setObject(1, id);
ResultSet rs = ps.executeQuery();
while (rs.next()) {

GoodsInfo gi = new GoodsInfo();
gi.setId(rs.getString("ID"));
gi.setName(rs.getString("NAME"));
gi.setPrice(rs.getDouble("PRICE"));
gi.setCompany(rs.getString("COMPANY"));
gi.setLeaveDate(rs.getString("LEAVE_DATE"));
gi.setDescription(rs.getString("DESCRIPTION"));
list.add(gi);
}
rs.close();
ps.close();
conn.close();

} catch (Exception ex) {
ex.printStackTrace();
throw new Exception();
}

return list;
}
}

3.购物车系统的接口ICartDao

package cn.hpe.dao;

import java.util.List;

import cn.hpe.po.CartInfo;
import cn.hpe.po.GoodsInfo;

public interface ICartDao {

/**
* 获得所有购物车商品
* @return
* @throws Exception
*/
public List<CartInfo> getAllCartList() throws Exception;


/**
* 更新购物车
*/
public int updateCart(String id) throws Exception ;


/**
* 新插入购物车
*/

public int addCart(GoodsInfo gi)throws Exception;
}

3.1购物车模块的实现类

package cn.hpe.dao.impl;

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

import cn.hpe.dao.BaseDao;
import cn.hpe.dao.ICartDao;
import cn.hpe.po.CartInfo;
import cn.hpe.po.GoodsInfo;

public class CartDaoImpl implements ICartDao {

/**
* 获得所有购物车商品
*
* @return
* @throws Exception
*/
@Override
public List<CartInfo> getAllCartList() throws Exception {

List<CartInfo> list = new ArrayList<CartInfo>();
try {
Connection conn = BaseDao.getConn();
String sql = "select * from TB_CART";
PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery();
while (rs.next()) {
CartInfo ci = new CartInfo();
ci.setID(rs.getString("id"));
ci.setNAME(rs.getString("name"));
ci.setNum(rs.getInt("num"));
ci.setPRICE(rs.getDouble("price"));
list.add(ci);
}
rs.close();
ps.close();
conn.close();

} catch (Exception e) {
e.printStackTrace();
throw new Exception();
}
return list;
}

/**
* 更新购物车信息
*/
@Override
public int updateCart(String id) throws Exception {
int r = 0;
try {
Connection conn = BaseDao.getConn();
String sql = "update TB_CART set num=num+1 where id=?";
PreparedStatement ps = conn.prepareStatement(sql);
ps.setObject(1, id);
r = ps.executeUpdate();
ps.close();
conn.close();
} catch (Exception e) {
e.printStackTrace();
throw new Exception();
}
return r;
}

/**
* 新插入购物车
*/
@Override
public int addCart(GoodsInfo gi) throws Exception {
int r = 0;
try {
Connection conn = BaseDao.getConn();
String sql = "insert into TB_CART values(?,?,?,?)";
PreparedStatement ps = conn.prepareStatement(sql);
ps.setObject(1, gi.getId());
ps.setObject(2, gi.getName());
ps.setObject(3, gi.getPrice());
ps.setObject(4, 1);
r = ps.executeUpdate();
ps.close();
conn.close();
} catch (Exception e) {
e.printStackTrace();
throw new Exception();
}
return r;
}

}

4.GoodsLsiyjsp模块

<%
GoodsDaoImpl gdl = new GoodsDaoImpl();
String currentPageStr = request.getParameter("page");
int currentPages = 1;
if (currentPageStr != null) {
currentPages = Integer.parseInt(currentPageStr);
}
int pageSizes = 3;
//获取总页数
int allPageList = gdl.getAllPage();
int allPage = (allPageList % pageSizes == 0) ? (allPageList / pageSizes)
: ((allPageList / pageSizes) + 1);

List<GoodsInfo> list = gdl.getGoodsList(currentPages, pageSizes);

//上一页
int prev = currentPages;
if (currentPages > 1) {
--prev;
} else if (currentPages == 1) {
prev = 1;
}
//下一页
int next = currentPages;
if (currentPages < allPage) {
++next;
} else if (currentPages == allPage) {
currentPages = allPage;
}
%>
<body>
<table align="center" border="1" cellpadding="0" cellspacing="0"
style="text-align: center;width: 50%">
<thead>
<th colspan="7"><h3 style="color: blue;font-weight: bold;margin-top: 20px">商品信息浏览</h3></th>
</thead>
<tbody>
<tr>
<td>编号</td>
<td>名称</td>
<td>价格</td>
<td>出厂日期</td>
<td>生产厂家</td>
<td>描述</td>
<td>操作</td>
</tr>
<%
for (GoodsInfo gi : list) {
%>
<tr>
<td><%=gi.getId()%></td>
<td><%=gi.getName()%></td>
<td><%=gi.getPrice()%></td>
<td><%=gi.getLeaveDate()%></td>
<td><%=gi.getCompany()%></td>
<td><%=gi.getDescription()%></td>
<td><a href="GoodsListCheck.jsp?id=<%=gi.getId()%>">点击购买</a></td>
</tr>
<%
}
%>
</tbody>
<tfoot>
<td colspan="7"><a href="GoodsList.jsp?page=1">首页</a><a
href="GoodsList.jsp?page=<%=prev%>">上一页</a><a
href="GoodsList.jsp?page=<%=next%>">下一页</a><a
href="GoodsList.jsp?page=<%=allPage%>">末页</a></td>
</tfoot>
</table>
</body>

4.1GoodsListCheck.jsp

<%
double money = 0;

GoodsDaoImpl gdl = new GoodsDaoImpl();
CartDaoImpl cdl = new CartDaoImpl();

String IdStr = request.getParameter("id");//获取要添加购物车的商品id

List<CartInfo> cartList = cdl.getAllCartList();//购物车
List<GoodsInfo> list = gdl.getAllGoodsList(IdStr);//商品列表

//将加入购物车的信息封装到GoodsInfo gi对象中
GoodsInfo gi = null;
for (GoodsInfo g : list) {
gi = new GoodsInfo();
gi.setId(g.getId());
gi.setName(g.getName());
gi.setPrice(g.getPrice());
}

//一个判断购物车表中是否已有要加入商品,没有执行add,已经存在执行update
boolean isNotFound = true;
for (CartInfo ci : cartList) {
if (ci.getID().equals(IdStr)) {
isNotFound = false;
break;

}
}

if (isNotFound) {
int r = cdl.addCart(gi);
if (r > 0) {
response.sendRedirect("Cart.jsp");
}
} else if (!isNotFound) {
int r = cdl.updateCart(IdStr);
if (r > 0) {
response.sendRedirect("Cart.jsp");
}
}
%>
<body>



</body>
</html>

4.2CartList.jsp

<%
double money = 0;
CartDaoImpl cdl = new CartDaoImpl();
List<CartInfo> cartList = cdl.getAllCartList();//购物车
%>
<body>
<table align="center" border="1" cellpadding="0" cellspacing="0"
style="text-align: center;width: 50%">
<thead>
<th colspan="5"><h3 style="color: blue;font-weight: bold;margin-top: 20px">我的购物车</h3></th>
</thead>
<tbody>
<tr>
<td>编号</td>
<td>名称</td>
<td>单价</td>
<td>数量</td>
<td>小计</td>
</tr>
<%
for (CartInfo cc : cartList) {
%>
<tr>
<td><%=cc.getID()%></td>
<td><%=cc.getNAME()%></td>
<td><%=cc.getPRICE()%></td>
<td><%=cc.getNum()%></td>
<td><%=cc.getPRICE() * cc.getNum()%></td>
<%
money += cc.getPRICE() * cc.getNum();
%>
</tr>

<%
}
%>
</tbody>
<thead>
<tr>
<td colspan="5">总计:<%=money%></td>
</tr>
<tr>
<td colspan="5"><a href="GoodsList.jsp">返回商品信息页面</a></td>
</tr>
</thead>
</table>
</body>
</html>

5数据库模块的两张表（商品表和购物车表）