Javaweb Core Programming (iii) Servlethello

About Servlet
The Java servlet is a server-side component that is not related to the peace platform and runs in a servlet container. The servlet container is responsible for the communication between the servlet and the client and calls the Servlet method, where the servlet container refers to the "request/response" pattern for Tomcat,servlet and client communication.
Servlets can perform the following functions:
--Create and return dynamic HTML pages based on customer requests
--Create a non-HTML page (HTML fragment) that can be embedded in an existing HTML page.
--Communicating with other server resources, such as databases or Java-based applications

Directly below the code

Create a new Dynamic Web project with the same first

Create Class Helloservlet.java

1  PackageCom.hello.testservlet;2 3 Importjava.io.IOException;4 5 ImportJavax.servlet.Servlet;6 ImportJavax.servlet.ServletConfig;7 Importjavax.servlet.ServletException;8 Importjavax.servlet.ServletRequest;9 ImportJavax.servlet.ServletResponse;Ten  One  Public classHelloServletImplementsServlet { A  - @Override -      Public voiddestroy () { the         //TODO auto-generated Method Stub -System.out.println ("Destory"); -     } -  + @Override -      PublicServletConfig Getservletconfig () { +         //TODO auto-generated Method Stub ASystem.out.println ("Getservletconfig"); at         return NULL; -     } -  - @Override -      PublicString Getservletinfo () { -         //TODO auto-generated Method Stub inSystem.out.println ("Getservletinfo"); -         return NULL; to     } +  - @Override the      Public voidInit (ServletConfig arg0)throwsservletexception { *         //TODO auto-generated Method Stub $System.out.println ("Init");Panax Notoginseng     } -  the @Override +      Public voidService (ServletRequest arg0, Servletresponse arg1)throwsservletexception, IOException { A         //TODO auto-generated Method Stub theSYSTEM.OUT.PRINTLN ("service"); +     } -  $      PublicHelloServlet () { $         Super(); -System.out.println ("HelloServlet ' s constructor"); -     } the      -     Wuyi  the}

Edit Web. xml file

1 <?XML version= "1.0" encoding= "UTF-8"?>2 <Web-appXmlns:xsi= "Http://www.w3.org/2001/XMLSchema-instance"xmlns= "Http://java.sun.com/xml/ns/javaee"xsi:schemalocation= "Http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"ID= "webapp_id"version= "3.0">3   <Display-name>HelloServlet</Display-name>4   5   <!--Note that Servlet-name needs to be consistent . -6   <servlet>7       <Servlet-name>Hellos</Servlet-name>8       <!--Full class name -9       <Servlet-class>Com.hello.testservlet.HelloServlet</Servlet-class>Ten   </servlet> One   <servlet-mapping> A       <Servlet-name>Hellos</Servlet-name> -       <!--Access Path - -       <Url-pattern>/hes</Url-pattern> the   </servlet-mapping> -    - </Web-app>

Right-click Project Run as->run on service

The browser accesses the http://localhost:8080/helloServlet/hes to see the following output in the console

1 helloservlet's constructor2init3service

Http://localhost:8080/helloServlet This part is the project root

The/hes configured in the Url-pattern property is the access path from the project root SIP

Javaweb Core Programming (iii) Servlethello