第一個servlet程序

1.編寫一個包，實現一個servlet類，繼承自httpservlet

package com.bzu.servlet;

import java.io.IOException;
import java.io.OutputStream;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class helloservlet extends HttpServlet {
    @Override
    protected void service(HttpServletRequest req, HttpServletResponse resp)
            throws ServletException, IOException {
        //根據響應，獲得一個輸出流
        OutputStream stream=resp.getOutputStream();
        //字符串轉化成字節數組，輸出一段字符串
        stream.write("sasa".getBytes());
    }
}

2.在web.xml中首先聲明servlet，然後做出外部訪問路徑的映射

<servlet>
   <servlet-name>helloservlet</servlet-name>
   <servlet-class>com.bzu.servlet.helloservlet</servlet-class>
</servlet>

<servlet-mapping>
    <servlet-name>helloservlet</servlet-name>
    <url-pattern>/hello</url-pattern>
</servlet-mapping>