Java Web开发之基于Session的购物商店实现方法

本文实例讲述了java web开发之基于session的购物商店实现方法。分享给大家供大家参考，具体如下：

package cn.com.shopping;
import java.io.ioexception;
import java.util.arraylist;
import java.util.list;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import javax.servlet.http.httpsession;
//完成购买
public class buyservlet extends httpservlet {
  private static final long serialversionuid = 1l;
  protected void doget(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {
    string id=request.getparameter("id");
    book book=(book)db.getall().get(id);
    //再加上那个关闭cookie时session的剞劂方案
    //阻止session的时候解决方案
    httpsession session=request.getsession(false);
    //从session中得到用户的保存所有书的集合（购物车）
    list list=(list)session.getattribute("list");
    if(list==null)
    {
      list=new arraylist();
      session.setattribute("list", list);
    }
    list.add(book);
    string url=response.encoderedirecturl("/session/sessioncountdemo");
    response.sendredirect(url);
  }
  protected void dopost(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {
    doget(request,response);
  }
}
package cn.com.shopping;
import java.io.ioexception;
import java.io.printwriter;
import java.util.linkedhashmap;
import java.util.map;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import javax.servlet.http.httpsession;
//显示书
public class listbookservlet extends httpservlet {
  private static final long serialversionuid = 1l;
  protected void doget(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {
    response.setcharacterencoding("utf-8");
    response.setcontenttype("text/html;charset=utf-8");
    printwriter out=response.getwriter();
    httpsession session=request.getsession();
    out.print("本店有如下的商品：<br/>");
    map<string ,book > map=db.getall();
    for(map.entry<string, book> entry:map.entryset())
    {
      book book=entry.getvalue();
      string url=response.encodeurl("/session/buyservlet?id="+book.getid());
      out.print(book.getname()+"<a href='"+url+"' target='_blank' >购买</a><br/>");
    }
  }
  protected void dopost(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {
    doget(request,response);
  }
}
//db作为数据库
class db
{
  private static map<string ,book> map=new linkedhashmap();
  static
  {
    map.put("1", new book("1","java web开发","wy","好书"));
    map.put("2", new book("2","web开发","zt","一般"));
    map.put("3", new book("3","程序设计","df","较好书"));
    map.put("4", new book("4","计算机组成","as","一般好书"));
    map.put("5", new book("5","编译原理","ty","很好书"));
    map.put("6", new book("6","网络维护","hj","非常好书"));
  }
  public static map getall()
  {
    return map;
  }
}
//书
class book
{
  private string id;
  private string name;
  private string author;
  private string description;
  public book() {
    super();
    // todo auto-generated constructor stub
  }
  public book(string id, string name, string author, string description) {
    super();
    this.id = id;
    this.name = name;
    this.author = author;
    this.description = description;
  }
  public string getid() {
    return id;
  }
  public void setid(string id) {
    this.id = id;
  }
  public string getname() {
    return name;
  }
  public void setname(string name) {
    this.name = name;
  }
  public string getauthor() {
    return author;
  }
  public void setauthor(string author) {
    this.author = author;
  }
  public string getdescription() {
    return description;
  }
  public void setdescription(string description) {
    this.description = description;
  }
}
package cn.com.shopping;
import java.io.ioexception;
import java.io.printwriter;
import java.util.list;
import javax.servlet.servletexception;
import javax.servlet.http.httpservlet;
import javax.servlet.http.httpservletrequest;
import javax.servlet.http.httpservletresponse;
import javax.servlet.http.httpsession;
public class sessioncountdemo extends httpservlet {
  private static final long serialversionuid = 1l;
  protected void doget(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {
    response.setcharacterencoding("utf-8");
    response.setcontenttype("text/html;charset=utf-8");
    printwriter out=response.getwriter();
    httpsession session=request.getsession();
    if(session==null)
    {
      out.write("您没买任何的商品！");
      return;
    }
    out.write("您购买了如下的商品：");
    list<book> list=(list) session.getattribute("list");
    for(book book:list)
    {
      out.write(book.getname());
    }
  }
  protected void dopost(httpservletrequest request, httpservletresponse response) throws servletexception, ioexception {
    doget(request,response);
  }
}

希望本文所述对大家java web程序设计有所帮助。