javaweb之统计网站访问量小案例

效果图

图片.png

项目目录:

图片.png

图片.png

切换浏览器，数据连续累加（全局作用域，服务器不重启，数据会一直保留）

html代码

    
hello world!
    click1

CountServlet代码

protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        
        request.setCharacterEncoding("UTF-8");
        response.setHeader("Content-Type ","text/html;charset=UTF-8");
        response.setContentType("text/html;charset=UTF-8");
        
        
    
        response.getWriter().append("Served at: ").append(request.getContextPath());
        PrintWriter out= response.getWriter();
        out.print("hello world!");
        
        
        ServletContext  context =this.getServletContext();
        Integer count=(Integer) context.getAttribute("counter");
        if(count==null) {
            count=1;
            context.setAttribute("counter", count+1);
        }
        
        request.getServletContext().setAttribute("counter",count+1);
        response.getWriter().println("网站访问量为："+count);  
        
    /*  response.setContentType("text/html");
        response.setCharacterEncoding("UTF-8");
        
        out.println("" + 
                "");
        out.println("");
        
        out.println("");
        out.println("
");
        out.println("you are num:"+context.getAttribute("counter"));
        out.println("
");
        out.println("");
        out.println("");*/
        
        out.flush();
        out.close();
        
    
        
        /*int totalCount=1;
        //默认访问量为1
        
        Object count = request.getServletContext().getAttribute("Faker");
           //判断count是否为null，不为null表示曾经访问过，直接将count赋值给totalCount
        
        if(count!=null) {
            totalCount=(int)count;
        }
        
        //访问次数累加
                request.getServletContext().setAttribute("Faker",totalCount+1);
                response.getWriter().println("网站访问量为："+totalCount); 
                
                
        //输出到界面
*/      
    }

参考:https://blog.csdn.net/qq_42813491/article/details/87807132