servlet入门

1.在tomcat中新建一个test应用，然后在web应用中新建一个web-inf/classes目录
2.在classes目录中新建一个FirstServlet.java

package cn.itcast;

import java.io.*;
import javax.servlet.*;
public class FirstServlet extends GenericServlet{

public void service(ServletRequest req,ServletResponse res) throws ServletException,java.io.IOException{
OutputStream out = res.getOutputStream();
out.write("hello servlet!!!".getBytes());
}

}

3.set classpath=%classpath%;C:apachelibservlet-api.jar 编译servlet

4.在web-inf目录中新建一个web.xml文件，配置servlet的对外访问路径

<?xml version="1.0" encoding="ISO-8859-1"?>

<web-app 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"
version="2.5">

<servlet>
<servlet-name>FirstServlet</servlet-name>
<servlet-class>cn.itcast.FirstServlet</servlet-class>
</servlet>

<servlet-mapping>
<servlet-name>FirstServlet</servlet-name>
<url-pattern>/FirstServlet</url-pattern>
</servlet-mapping>

</web-app>

5.启动tomcat，访问