servlet初体验

开发Servlet
1.在webapps目录下新建一个helloservlet的web应用，在helloservlet目录下新建一个WEB-INF目录下创建classes，在classes下新建FirstServlet.java
package jb.helloservlet.servlet;
import java.io.*;
import javax.servlet.*;
public class FirstServlet extends GenericServlet{
 public void service(ServletRequest req,ServletResponse res)
  throws ServletException,java.io.IOException{
  String data="hello servlet";
  OutputStream out=res.getOutputStream();
  out.write(data.getBytes());
 }
}
2.配置环境变量：classpath：D:\soft\Tomcat 6.0\bin;D:\soft\Tomcat 6.0\lib\servlet-api.jar
3.开始-》运行-》cmd-》进入到webapps\helloservlet\WEB-INF\classes，编译FirstServlet.java
javac -d . FirstServlet.java
4.在helloservlet的WEB-INF目录下，新建web.xml文件，对servlet进行配置：
<?xml version="1.0" encoding="UTF-8"?>
<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>jb.helloservlet.servlet.FirstServlet</servlet-class>
    </servlet>
    
    
     <servlet-mapping>
        <servlet-name>FirstServlet</servlet-name>
        <!-- /代表web工程 也就是helloservlet -->
        <url-pattern>/first</url-pattern>
    </servlet-mapping>
    <welcome-file-list>
    <welcome-file>index.html</welcome-file>
    <welcome-file>index.htm</welcome-file>
    <welcome-file>index.jsp</welcome-file>
    </welcome-file-list>
</web-app>
5.启动tomcat服务器：
http://localhost:8080/helloservlet/first