1.新建项目是project - web - Dynamic Web Project
2.在新建项目public class HelloServlet extends HttpServlet下右键选择source - Override/Implement Methods... 选择两个init service(http那个) 和 destroy
3.service下
PrintWriter pw = arg1.getWriter();
pw.println("hello world");
pw.close();
4.web Content - WEB INF - web xml 下
<servlet>
` <servlet - name> 某个字符串</servlet - name>
<servlet - class> 上面的class类名 </servlet - class>
</servlet>
<servlet - mapping>
<servlet - name>某个字符串</servlet - name>
<url - pattern>/某个字符串(/不要忘记)</url - pattern>
</servlet - mapping>
5.运行tomcat
在浏览器中输入http://localhost:8080/项目名称/前面/后面的字符串