如何处理java高并发问题---之页面静态化

解决java中的高并发问题可以从硬件软件等方面入手，硬件如：服务器；软件如：系统缓存、页面静态化等。这里我写的是页面静态化的简单小例子。之所以将这个小例子记录下来是因为之前对页面静态化有误解，原以为静态化页面就是在项目编写中前端页面利用html就可以。但是在参考网上资料后发现理解误差很大，以下是我在参考了一些网上资料后写的实现页面静态化的简单实例：

项目结构图

1.业务处理类Servlet.java（这里为了方便采用的servlet，可根据项目需求在其他的架构中使用其中的业务逻辑）

package com.servlet;import java.io.File;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;public class Servlet extends HttpServlet{public void service(HttpServletRequest request,HttpServletResponse response) throws ServletException, IOException{System.out.println("chapterId=====//===="+request.getParameter("chapterId"));if(request.getParameter("chapterId")!= null){        String chapterFileName = "bookChapterRead_"+request.getParameter("chapterId")+".html";          String chapterFilePath = getServletContext().getRealPath("/") + chapterFileName;         System.out.println("chapterFilePath===//============="+chapterFilePath);        File chapterFile = new File(chapterFilePath);        System.out.println("chapterFile===//============="+chapterFile);        if(chapterFile.exists()){//如果有这个文件就告诉浏览器转向        System.out.println("有此静态页面＝＝＝＝＝＝");        response.sendRedirect(chapterFileName);        return;          }        System.out.println("没有此静态页面＝＝＝＝＝＝");        //======存放业务处理后得到的信息        request.setAttribute("novelChapter", "测试单节信息");        request.setAttribute("lastPageId", "lastPageId111");        request.setAttribute("nextPageId", "nextPageId222");        //============        System.out.println("getServletContext()==========//========="+getServletContext());        new CreateStaticHTMLPage().createStaticHTMLPage(request, response, getServletContext(),                chapterFileName, chapterFilePath, "/bookRead.jsp");    }}}

２.创建静态页面类CreateStaticHTMLPage.java

package com.servlet;import java.io.ByteArrayOutputStream;import java.io.FileOutputStream;import java.io.IOException;import java.io.OutputStreamWriter;import java.io.PrintWriter;import javax.servlet.RequestDispatcher;import javax.servlet.ServletContext;import javax.servlet.ServletException;import javax.servlet.ServletOutputStream;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpServletResponseWrapper;/** * 创建HTML静态页面 * 功能：创建HTML静态页面 */  public class CreateStaticHTMLPage { /**     * 生成静态HTML页面的方法      * @param request 请求对象     * @param response 响应对象     * @param servletContext Servlet上下文     * @param fileName 文件名称     * @param fileFullPath 文件完整路径     * @param jspPath 需要生成静态文件的JSP路径(相对即可)     * @throws IOException     * @throws ServletException     */public void createStaticHTMLPage(HttpServletRequest request, HttpServletResponse response,ServletContext servletContext,String fileName,String fileFullPath,String jspPath) throws ServletException, IOException{          response.setContentType("text/html;charset=utf-8");//设置HTML结果流编码(即HTML文件编码)           RequestDispatcher rd = servletContext.getRequestDispatcher(jspPath);//得到JSP资源        final ByteArrayOutputStream byteArrayOutputStream = new ByteArrayOutputStream();//用于从ServletOutputStream中接收资源           final ServletOutputStream servletOuputStream = new ServletOutputStream(){//用于从HttpServletResponse中接收资源               public void write(byte[] b, int off,int len){                byteArrayOutputStream.write(b, off, len);              }              public void write(int b){                byteArrayOutputStream.write(b);            }          };          final PrintWriter printWriter = new PrintWriter(new OutputStreamWriter(byteArrayOutputStream));//把转换字节流转换成字符流           HttpServletResponse httpServletResponse = new HttpServletResponseWrapper(response){//用于从response获取结果流资源(重写了两个方法)               public ServletOutputStream getOutputStream(){                return servletOuputStream;              }            public PrintWriter getWriter(){                return printWriter;              }        };          rd.include(request, httpServletResponse);//发送结果流           printWriter.flush();//刷新缓冲区，把缓冲区的数据输出           FileOutputStream fileOutputStream = new FileOutputStream(fileFullPath);          byteArrayOutputStream.writeTo(fileOutputStream);//把byteArrayOuputStream中的资源全部写入到fileOuputStream中           fileOutputStream.close();//关闭输出流，并释放相关资源           response.sendRedirect(fileName);//发送指定文件流到客户端       }}

３.web.xml配置文件

<?xml version="1.0" encoding="UTF-8"?><web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"><servlet>  <servlet-name>htmlServlet</servlet-name>  <servlet-class>com.servlet.Servlet</servlet-class></servlet><servlet-mapping>  <servlet-name>htmlServlet</servlet-name>  <url-pattern>*.do</url-pattern></servlet-mapping>  <welcome-file-list>    <welcome-file>index.jsp</welcome-file>  </welcome-file-list></web-app>

４.首页面index.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>    <base href="<%=basePath%>">        <title>首页面</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>   <form action="kanName.do">     <input name="chapterId" type="text" value="122"/>     <input name="userName" type="text" value="张庆伟"/>     <input type="submit" value="提交"/>   </form>  </body></html>

5.跳转后的结果页面bookRead.jsp

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html>  <head>  <%    String lastPageId=(String)request.getAttribute("lastPageId");  %>    <base href="<%=basePath%>">        <title>book页</title><meta http-equiv="pragma" content="no-cache"><meta http-equiv="cache-control" content="no-cache"><meta http-equiv="expires" content="0">    <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"><meta http-equiv="description" content="This is my page"><!--<link rel="stylesheet" type="text/css" href="styles.css">-->  </head>    <body>  这是跳转页面：   <%=lastPageId %>  </body></html>

以上代码是实例的所有代码，启动项目后点击提交按钮后，会看到跳转到一个html页面。

以上代码参考自：http://blog.csdn.net/jimmy609/article/details/37810591