JAVA---Servlet2

package servlet;

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

/**
 * @create 2022-04-23 15:40
 */
public class ParameterServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("------------get-----------");
        //获取请求参数
        String username = req.getParameter("username");
        String password = req.getParameter("password");
        String[] hobby = req.getParameterValues("hobby");

        System.out.println("用户名"+username);
        System.out.println("密码"+password);
        System.out.println("兴趣爱好"+ Arrays.asList(hobby));
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        
        req.setCharacterEncoding("UTF-8");
        System.out.println("------------post-----------");
        //获取请求参数
        String username = req.getParameter("username");
        String password = req.getParameter("password");
        String[] hobby = req.getParameterValues("hobby");

        System.out.println("用户名"+username);
        System.out.println("密码"+password);
        System.out.println("兴趣爱好"+ Arrays.asList(hobby));
    }
}

package servlet;

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

/**
 * @create 2022-04-23 15:28
 */
public class RequestAPIServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取请求的资源路径
        System.out.println("UTI---》"+req.getRequestURI());
        //获取请求的统一资源定位符（绝对路径）
        System.out.println("URL--->"+req.getRequestURL());
        //获取ip地址
        System.out.println("客户端 IP地址"+req.getRemoteHost());
        //获取请求头
        System.out.println("请求头---》"+req.getHeader("User-Agent"));
        //获取请求的方式GET或POST
        System.out.println("请求的方式："+req.getMethod());
    }
}

package servlet;

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

/**
 * @create 2022-04-23 16:57
 */
public class Response1 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println("response1");
        req.setAttribute("key1","value1");
        
        resp.sendRedirect("http://localhost:8080/07_servlet2/response2");
    }
}

package servlet;

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

/**
 * @author nkc
 * @create 2022-04-23 17:00
 */
public class Response2 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        System.out.println(req.getAttribute("key1"));
        resp.getWriter().write("response2!!!!!");
    }
}

package servlet;

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

/**
 * @create 2022-04-23 16:50
 */
public class ResponseIOServlet extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        resp.setContentType("text/html;charset=UTF-8");
        PrintWriter writer = resp.getWriter();
        writer.write("你好！");
    }
}

package servlet;

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

/**
 * 
 * 
 * @create 2022-04-23 16:11
 */
public class Servlet1 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        //获取请求的参数
        String username = req.getParameter("username");
        System.out.println("在servlet1中："+username);
        
        req.setAttribute("key1","servlet1");
        
        //请求转发
        RequestDispatcher requestDispatcher = req.getRequestDispatcher("/servlet2");
        
        requestDispatcher.forward(req,resp);
    }
    
}

package servlet;

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

/**
 * 
 * 
 * @create 2022-04-23 16:32
 */
public class Servlet2 extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String username = req.getParameter("username");
        System.out.println("在servlet2中："+username);

        Object key1 = req.getAttribute("key1");
        System.out.println("是否是servlet1："+key1);

        System.out.println("Servlet2开始工作...");
    }
}

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
    
    <servlet>
        <servlet-name>RequestAPIServlet</servlet-name>
        <servlet-class>servlet.RequestAPIServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>RequestAPIServlet</servlet-name>
        <url-pattern>/requestAPIServlet</url-pattern>
    </servlet-mapping>
    
    <servlet>
        <servlet-name>ParameterServlet</servlet-name>
        <servlet-class>servlet.ParameterServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>ParameterServlet</servlet-name>
        <url-pattern>/parameterServlet</url-pattern>
    </servlet-mapping>
    
    <servlet>
        <servlet-name>Servlet1</servlet-name>
        <servlet-class>servlet.Servlet1</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Servlet1</servlet-name>
        <url-pattern>/servlet1</url-pattern>
    </servlet-mapping>
    
    <servlet>
        <servlet-name>Servlet2</servlet-name>
        <servlet-class>servlet.Servlet2</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Servlet2</servlet-name>
        <url-pattern>/servlet2</url-pattern>
    </servlet-mapping>
    
    <servlet>
        <servlet-name>ResponseIOServlet</servlet-name>
        <servlet-class>servlet.ResponseIOServlet</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>ResponseIOServlet</servlet-name>
        <url-pattern>/responseIOServlet</url-pattern>
    </servlet-mapping>
    
    
    <servlet>
        <servlet-name>Response1</servlet-name>
        <servlet-class>servlet.Response1</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Response1</servlet-name>
        <url-pattern>/response1</url-pattern>
    </servlet-mapping>
    
    <servlet>
        <servlet-name>Response2</servlet-name>
        <servlet-class>servlet.Response2</servlet-class>
    </servlet>
    <servlet-mapping>
        <servlet-name>Response2</servlet-name>
        <url-pattern>/response2</url-pattern>
    </servlet-mapping>
    
</web-app>