Eclipse Development servlet+jsp Model of the simple counter 1, click File->javaproject->tomcatproject, input project name; 2, under the project to create a new index.jsp page as Home 3, in the Web-inf directory to create a new Web.xm file, write the following content. 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 >countservlet </servlet-name >
< Servlet-class >cn.sdut.chenqiang.countservlet </servlet-class >
</servlet >
< servlet-mapping >
< Servlet-name >countservlet </servlet-name >
< Url-pattern >/countservlet </url-pattern >
</servlet-mapping >
< Welcome-file-list >
< Welcome-file >index.jsp </welcome-file >
</welcome-file-list >
</Web-app > 4, New Class Countservlet in Src directory, inheriting httpservlet package Cn.sdut.chenqiang;
Import java.io.IOException;
Import Java.io.PrintWriter;
Import Javax.servlet.ServletConfig;
Import Javax.servlet.ServletContext;
Import javax.servlet.ServletException;
Import Javax.servlet.http.HttpServlet;
Import Javax.servlet.http.HttpServletRequest;
Import Javax.servlet.http.HttpServletResponse;
public class Countservlet extends HttpServlet {
public static final String content_type= "Text/html;charset=utf-8";
@Override
public void init (ServletConfig config) throws servletexception {
TODO auto-generated Method Stub
Super.init (config);
}
@Override
protected void Doget (HttpServletRequest req, HttpServletResponse resp)
Throws Servletexception, IOException {
TODO auto-generated Method Stub
DoPost (req, resp);
}
@Override
protected void DoPost (HttpServletRequest req, HttpServletResponse resp)
Throws Servletexception, IOException {
TODO auto-generated Method Stub
ServletContext context = Getservletcontext ();
Integer count = (integer) context.getattribute ("Count");
if (count== null)
{
Count = new Integer (0);
Context.setattribute ("Count", new Integer (0));
}
Resp.setcontenttype (Content_Type);
PrintWriter out = Resp.getwriter ();
Out.println ("<HTML>");
Out.println ("<HEAD><TITLE> click Count </TITLE></HEAD>");
Out.println ("<BODY>");
Out.println ("<p> Current count is:" +count+ "</p>");
Out.println ("</BODY></HEAD>");
Count = new Integer (Count.intvalue () +1);
Context.setattribute ("Count", count);
}
@Override
public void Destroy () {
TODO auto-generated Method Stub
Super.destroy ();
}
}
5, run can
