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");
}
}
}
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
}
}
htmlServlet
com.servlet.Servlet
htmlServlet
*.do
index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
首页面
<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<%
String lastPageId=(String)request.getAttribute("lastPageId");
%>
book页
这是跳转页面:
<%=lastPageId %>
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