web项目有目录结构要求
WEB-INFO 文件夹 是一个Servlet规范,必须要这么命名,在换个文件夹里面如果创建一个jsp文件是不能直接访问的,在WEB-INfO文件夹之外创建的jsp可以直接访问
WEB-INFO下也有目录结构要求,如下图
web.xml
Servlet是个接口,接口有5个必须实现的方法
想实现java web 必须实现这5个方法destroy() getServletConfig() getServletInfo() init(ServletConfig config) service(ServletRequest req,ServletResponse res)
以下为输出到浏览器窗口的代码
import javax.servlet.Servlet;
import javax.servlet.ServletConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import java.io.IOException;
import java.io.PrintWriter; public class WelcomeServlet implements Servlet
{
public void init(ServletConfig config) throws ServletException
{ } public void service(ServletRequest request,ServletResponse response) throws ServletException,IOException
{ PrintWriter out=response.getWriter();
out.print("123123");
} public void destroy(){}
public String getServletInfo(){return null;}
public ServletConfig getServletConfig(){return null;} }
配置xml
<?xml version="1.0" encoding="ISO-8859-1"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee
http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
version="3.1"> <servlet>
<servlet-name>thisIsServletName</servlet-name>
<servlet-class>WelcomeServlet</servlet-class>
</servlet> <servlet-mapping>
<servlet-name>thisIsServletName</servlet-name>
<url-pattern>/aaa</url-pattern>
</servlet-mapping> </web-app>