mvc购物车项目--提交订单并创建订单

SubmitOrderServlet.java

public class SubmitOrderServlet extends HttpServlet {
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html;charset=utf-8");
		PrintWriter out = response.getWriter();
		//该servlet要处理下订单的请求
		try {
			OrderService orderservice=new OrderService();
			MyCart myCart=(MyCart)request.getSession().getAttribute("myCart");
			Users user=(Users)request.getSession().getAttribute("loginUser");
			orderservice.submitOrder(myCart, user);
		} catch (Exception e) {
			e.printStackTrace();
			request.getRequestDispatcher("/WEB-INF/errInfo.jsp");
			// TODO: handle exception
		}
		//如果订单写入到数据库，把邮件发送给客户
		SendMailToSomeone sts=new SendMailToSomeone();
		Users user=(Users)request.getSession().getAttribute("loginUser");
		System.out.println(user.getEmail());
		sts.send("购物确认",
				"<meta http-equiv=content-Type content=text/html;charset=gb2312><div align=center><h1 style=\"color: red\">"+user.getName()+"在XX网订购了一份商品</h1></div>",
				user.getEmail(),
				"[email protected]",
				"wx",
				"smtp.sohu.com");

		request.getRequestDispatcher("/WEB-INF/OrderOk.jsp").forward(request, response);
	}
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		response.setContentType("text/html");
		PrintWriter out = response.getWriter();
		this.doGet(request, response);
	}
}

调用了OrderService类

OrderService.java

package com.wxh.service;
import java.sql.*;
import java.util.ArrayList;
import javax.management.RuntimeErrorException;
import com.wxh.domain.Book;
import com.wxh.domain.Users;
import com.wxh.utils.DBUtil;

//处理与订单相关的业务逻辑
public class OrderService {
	private Connection ct=null;
	private PreparedStatement ps=null;
	private ResultSet rs=null;	

	//下订单涉及到两张表,而且两张表有关系
	public void submitOrder(MyCart myCart,Users user){
		String sql="insert into orders values(order_seq.nextval,?,?,sysdate)";
		//因为添加订单复杂，所以这种操作很特别，于是自己写一个。
		try {
			ct=DBUtil.getCon();
			//为了保证订单号是稳定的，所以将其事务隔离级别升级(可串行)
			ct.setAutoCommit(false);
			ct.setTransactionIsolation(Connection.TRANSACTION_SERIALIZABLE);
			ps=ct.prepareStatement(sql);
			ps.setInt(1,user.getId());
			ps.setFloat(2, user.getId());
			ps.executeUpdate();
			//如何得到刚刚插入的订单记录的订单号
			sql="select order_seq.currval from orders";
			ps=ct.prepareStatement(sql);
			rs=ps.executeQuery();
			int orderId=0;
			if(rs.next()){
				//取出刚刚生成的订单号
				orderId=rs.getInt(1);
			}
			//把订单细节表生成（批量提交）
			ArrayList al=myCart.showMyCart();
			for(int i=0;i<al.size();i++){
				Book book=(Book)al.get(i);
				sql="insert into orderitem values(orderitem_seq.nextval,?,?,?)";
				ps=ct.prepareStatement(sql);
				ps.setInt(1, orderId);
				ps.setInt(2, book.getId());
				ps.setInt(3, book.getShoppingNum());
				ps.executeUpdate();
			}
			//整体提交
			ct.commit();
		} catch (Exception e) {
			// TODO: handle exception
			try {
				ct.rollback();
			} catch (Exception e1) {
				// TODO: handle exception
				e1.printStackTrace();
			}
			//e.printStackTrace();
			throw new RuntimeException(e.getMessage());
		}finally{
			DBUtil.close(rs, ps, ct);
		}
	}
}

——摘自《韩顺平细说jsp》