动态jsp生成静态html网页

时间:2022-11-11 22:15:51

 网站提高性能的方案有很多,网站架构方面考虑,最初的性能优化可以考虑提高单台服务器的配置。把数据库

和代码分别部署在两台服务器,页面缓存,数据缓存,静态化,分布式,代码读写分离,负载均衡。这些东西都是大型网站发展

所必须经历的升级过程,前两种方案非常容易实现,页面缓存J2EE中用的不多,数据缓存可以借助hibernate提供的第三方支持,

分布式和读写分离,我的方案是使用EJB3,均衡负载可由Apache+Tomcat提供,本文简单说一下页面静态化技术,

也就是jsp通过html模板生成html页面,比较高级点的处理就是让它自动静态化,其实无论使用什么框架原理都是相通的。我就刨开

框架的束缚,用最基础的servlet和jsp实现,自动静态化技术。

      需要一个过滤器(Servlet)实现何时静态化的判断,还需要一个jsp页面实现静态化业务,然后需要静态化页面的模板

(html),一个文件流操作类。

模板页

 

动态jsp生成静态html网页动态jsp生成静态html网页
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
    
<head>
    
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
        
<title>My JSP 'index.jsp' starting page</title>
    
</head>
    
<body>
        
<center>
            
<href="../index.jsp">返回首页</a>
        
</center>
        
<div align="center">
            
<table width="40%" border="1" bordercolor="#000000">
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        编号:
                    
</td>
                    
<td bordercolor="#FFFFFF">###i1###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        标题:
                    
</td>
                    
<td bordercolor="#FFFFFF">###title1###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        作者:
                    
</td>
                    
<td bordercolor="#FFFFFF">###author1###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        发布日期:
                    
</td>
                    
<td bordercolor="#FFFFFF">###release_date1###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        内容:
                    
</td>
                    
<td bordercolor="#FFFFFF"><href="./showDetail.jsp?id=###id1###">查看详细新闻</a></td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        
<href="./editNews.jsp?id=###id1###">修改</a>&nbsp;&nbsp;&nbsp;
                        
<href="./deleteNewsHandler.jsp?id=###id1###">删除</a>
                    
</td>
                
</tr>
            
</table>
            
<br>
            
<table width="40%" border="1" bordercolor="#000000">
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        编号:
                    
</td>
                    
<td bordercolor="#FFFFFF">###i2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        标题:
                    
</td>
                    
<td bordercolor="#FFFFFF">###title2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        作者:
                    
</td>
                    
<td bordercolor="#FFFFFF">###author2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        发布日期:
                    
</td>
                    
<td bordercolor="#FFFFFF">###release_date2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        内容:
                    
</td>
                    
<td bordercolor="#FFFFFF"><href="./showDetail.jsp?id=###id2###">查看详细新闻</a></td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        
<href="./editNews.jsp?id=###id2###">修改</a>&nbsp;&nbsp;&nbsp;
                        
<href="./deleteNewsHandler.jsp?id=###id2###">删除</a>
                    
</td>
                
</tr>
            
</table>
            
<br>
            
<table width="40%" border="1" bordercolor="#000000">
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        编号:
                    
</td>
                    
<td bordercolor="#FFFFFF">###i2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        标题:
                    
</td>
                    
<td bordercolor="#FFFFFF">###title2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        作者:
                    
</td>
                    
<td bordercolor="#FFFFFF">###author2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        发布日期:
                    
</td>
                    
<td bordercolor="#FFFFFF">###release_date2###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        内容:
                    
</td>
                    
<td bordercolor="#FFFFFF"><href="./showDetail.jsp?id=###id2###">查看详细新闻</a></td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        
<href="./editNews.jsp?id=###id2###">修改</a>&nbsp;&nbsp;&nbsp;
                        
<href="./deleteNewsHandler.jsp?id=###id2###">删除</a>
                    
</td>
                
</tr>
            
</table>
            
<br>
            
<table width="40%" border="1" bordercolor="#000000">
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        编号:
                    
</td>
                    
<td bordercolor="#FFFFFF">###i3###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        标题:
                    
</td>
                    
<td bordercolor="#FFFFFF">###title3###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        作者:
                    
</td>
                    
<td bordercolor="#FFFFFF">###author3###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        发布日期:
                    
</td>
                    
<td bordercolor="#FFFFFF">###release_date3###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        内容:
                    
</td>
                    
<td bordercolor="#FFFFFF"><href="./showDetail.jsp?id=###id3###">查看详细新闻</a></td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        
<href="./editNews.jsp?id=###id3###">修改</a>&nbsp;&nbsp;&nbsp;
                        
<href="./deleteNewsHandler.jsp?id=###id3###">删除</a>
                    
</td>
                
</tr>
            
</table>
            
<br>
            
<table width="40%" border="1" bordercolor="#000000">
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        编号:
                    
</td>
                    
<td bordercolor="#FFFFFF">###i4###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        标题:
                    
</td>
                    
<td bordercolor="#FFFFFF">###title4###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        作者:
                    
</td>
                    
<td bordercolor="#FFFFFF">###author4###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        发布日期:
                    
</td>
                    
<td bordercolor="#FFFFFF">###release_date4###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        内容:
                    
</td>
                    
<td bordercolor="#FFFFFF"><href="./showDetail.jsp?id=###id4###">查看详细新闻</a></td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        
<href="./editNews.jsp?id=###id4###">修改</a>&nbsp;&nbsp;&nbsp;
                        
<href="./deleteNewsHandler.jsp?id=###id4###">删除</a>
                    
</td>
                
</tr>
            
</table>
            
<br>
            
<table width="40%" border="1" bordercolor="#000000">
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        编号:
                    
</td>
                    
<td bordercolor="#FFFFFF">###i5###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        标题:
                    
</td>
                    
<td bordercolor="#FFFFFF">###title5###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        作者:
                    
</td>
                    
<td bordercolor="#FFFFFF">###author5###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        发布日期:
                    
</td>
                    
<td bordercolor="#FFFFFF">###release_date5###</td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        内容:
                    
</td>
                    
<td bordercolor="#FFFFFF"><href="./showDetail.jsp?id=###id5###">查看详细新闻</a></td>
                
</tr>
                
<tr>
                    
<td bordercolor="#FFFFFF">
                        
<href="./editNews.jsp?id=###id5###">修改</a>&nbsp;&nbsp;&nbsp;
                        
<href="./deleteNewsHandler.jsp?id=###id5###">删除</a>
                    
</td>
                
</tr>
            
</table>
            
<br>
        
</div>
        
<br>
        
<br>
    
</body>
</html>
动态jsp生成静态html网页

                    

过滤器的过滤方法:

 

动态jsp生成静态html网页public void doFilter(ServletRequest request, ServletResponse response,
            FilterChain chain) 
throws IOException, ServletException {
        HttpServletRequest req 
= (HttpServletRequest) request;
        HttpServletResponse res 
= (HttpServletResponse) response;
        HttpSession session 
= req.getSession();

        
long timeNum = new Date().getTime();
        String strNum 
= String.valueOf(session.getAttribute("updateTime"));

        
if (null == strNum && strNum.equals("")) {
            
long Num = timeNum - Long.valueOf(strNum);
            
if (Num >= 7200000) {
                session.setAttribute(
"updateTime", String.valueOf(timeNum));
                res.sendRedirect(req.getContextPath() 
+ url);
                chain.doFilter(request, response);
            } 
        } 
else {
            session.setAttribute(
"updateTime", String.valueOf(timeNum));
            res.sendRedirect(req.getContextPath() 
+ url);
            chain.doFilter(request, response);
        }
        chain.doFilter(request, response);
    }
动态jsp生成静态html网页

 

jsp的处理核心方法:

 

动态jsp生成静态html网页String Modelpath = request.getRealPath("/"+ "/news/listNewsMoban.html"//模板文件地址
            String OutHTMLpath = request.getRealPath("/"+ "/news/listNews.html";//静态页文件地址

            
try {
                FileStreamHelp fsh 
= new FileStreamHelp();//实例化文件操作辅助类

                String htmlcode 
= fsh.ReadFile(Modelpath);//读取模板文件
                
                
int i = 0;
                List
<Object> listnews = new ArrayList<Object>();
                BaseDao dao 
= new NewsDaoImpl();
                
try {
                    listnews 
= dao.listObject();
                } 
catch (Exception e) {
                    e.printStackTrace();
                }
                Iterator
<Object> it = listnews.iterator();
                
while (it.hasNext() && i <= 5) {
                    News news 
= (News) it.next();
                    i
++;
                    htmlcode
=htmlcode.replaceAll("###i"+i+"###", String.valueOf(i));
                    htmlcode
=htmlcode.replaceAll("###title"+i+"###", news.getTitle());
                    htmlcode
=htmlcode.replaceAll("###author"+i+"###", news.getAuthor());
                    htmlcode
=htmlcode.replaceAll("###release_date"+i+"###", news.getRelease_date());
                    htmlcode
=htmlcode.replaceAll("###id"+i+"###",String.valueOf(news.getId()));
                    }
                
                fsh.WriteFile(htmlcode, OutHTMLpath);
//生成首页文件
            } catch (Exception e) {
                e.printStackTrace();
            }
            session.setAttribute(
"updateTime",new Date().getTime());
            response.sendRedirect(request.getContextPath() 
+ "/index.jsp");