Request对象的作用

1. 获取http请求行中信息：请求方式和请求路径
2. 获取客户端信息：如ip
3. 获取请求资源路径
4. 域对象

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 * Servlet implementation class RequestServlet
 */
public class RequestServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
    /**
     * @see HttpServlet#HttpServlet()
     */
    public RequestServlet() {
        super();
        // TODO Auto-generated constructor stub
    }

	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		//1、获取http请求行中信息：请求方式和请求路径
		System.out.println("请求方式"+request.getMethod());
		//URI:统一资源标识符
		System.out.println("请求路径"+request.getRequestURI());
		//URL：统一资源定位符
		System.out.println("请求路径"+request.getRequestURL());
		//2、获取客户端信息：如ip
		System.out.println("客户端ip"+request.getRemoteAddr());
		//3、获取请求资源路径
		System.out.println("项目名称"+request.getContextPath());
		//4、域对象
		//往request作用域存值      可以存任意类型
		request.setAttribute("name", "zhangsan");
		request.setAttribute("age", "18");
		request.setAttribute("sex", "男");
		//从request作用域取值 注意：一次请求有效
		System.out.println(request.getAttribute("name"));
		System.out.println(request.getAttribute("age"));
		System.out.println(request.getAttribute("sex"));
		
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
	}

}