WEB24_Filter

男娘i 2022-02-28 12:20 122阅读 0赞

## 一、过滤器简介 ##

filter是对客户端访问资源的过滤，符合条件放行，不符合条件不放行，并且可以对目标资源访问前后进行逻辑处理。  
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## 二、过滤器快速入门 ##

实现步骤：  
（1）编写一个过滤器的类实现Filter接口  
（2）实现接口中尚未实现的方法(着重实现doFilter方法)  
（3）在web.xml中进行配置(主要是配置要对哪些资源进行过滤)  
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com.itcast.filter.QuickFilter

package com.itcast.filter;
    
    import java.io.IOException;
    
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.FilterConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    
    public class QuickFilter implements Filter{
    
    	@Override
    	public void init(FilterConfig filterConfig) throws ServletException {
    		
    	}
    
    	@Override
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
    			throws IOException, ServletException {
    		System.out.println("quick running...");
    		//放行请求
    		chain.doFilter(request, response);
    	}
    
    	@Override
    	public void destroy() {
    		
    	}
    	
    }

web.xml

<?xml version="1.0" encoding="UTF-8"?>
    <web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
      <display-name>WEB24</display-name>
      <filter>
        <filter-name>QuickFilter</filter-name>
        <filter-class>com.itcast.filter.QuickFilter</filter-class>
      </filter>
      <filter-mapping>
        <filter-name>QuickFilter</filter-name>
        <url-pattern>/*</url-pattern>
      </filter-mapping>
      <welcome-file-list>
        <welcome-file>index.html</welcome-file>
        <welcome-file>index.htm</welcome-file>
        <welcome-file>index.jsp</welcome-file>
        <welcome-file>default.html</welcome-file>
        <welcome-file>default.htm</welcome-file>
        <welcome-file>default.jsp</welcome-file>
      </welcome-file-list>
      <servlet>
        <description></description>
        <display-name>Servlet1</display-name>
        <servlet-name>Servlet1</servlet-name>
        <servlet-class>com.itcast.servlet.Servlet1</servlet-class>
      </servlet>
      <servlet-mapping>
        <servlet-name>Servlet1</servlet-name>
        <url-pattern>/servlet1</url-pattern>
      </servlet-mapping>
    </web-app>

com.itcast.servlet.Servlet1

package com.itcast.servlet;
    
    import java.io.IOException;
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    public class Servlet1 extends HttpServlet {
    
    	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		response.getWriter().write("Servlet1 running...");
    	}
    
    	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		doGet(request, response);
    	}
    }

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## 三、Filter的API详解 ##

### (1) filter生命周期及其与生命周期相关的方法 ###

Filter接口有三个方法，并且这个三个都是与Filter的生命相关的方法  
init(Filterconfig)：代表filter对象初始化方法 filter对象创建时执行  
doFilter(ServletRequest,ServletResponse,FilterCha)：代表filter执行过滤的核心方法，如果某资源在已经被配置到这个filter进行过滤的话，那么每次访问这个资源都会执行doFilter方法  
destory()：代表是filter销毁方法 当filter对象销毁时执行该方法

#### Filter对象的生命周期： ####

Filter何时创建：服务器启动时就创建该filter对象  
Filter何时销毁：服务器关闭时filter销毁  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 4]  
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### (2) Filter的AP详解 ###

#### 1）init(FilterConfig) ####

其中参数config代表 该Filter对象的配置信息的对象，内部封装是该filter的配置信息。

<filter>
        <filter-name>QuickFilter1</filter-name>
        <filter-class>com.itcast.filter.QuickFilter1</filter-class>
        <init-param>
        	<param-name>aaa</param-name>
        	<param-value>AAAAA</param-value>
        </init-param>
      </filter>
      <filter-mapping>
        <filter-name>QuickFilter1</filter-name>
        <url-pattern>/*</url-pattern>
      </filter-mapping>

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#### 2）destory()方法 ####

filter对象销毁时执行

#### 3）doFilter方法 ####

doFilter(ServletRequest,ServletResponse,FilterChain)  
其中的参数：  
ServletRequest/ServletResponse：每次在执行doFilter方法时 web容器负责创建一个request和一个response对象作为doFilter的参数传递进来。该request个该response就是在访问目标资源的service方法时的request和response。  
FilterChain：过滤器链对象，通过该对象的doFilter方法可以放行该请求

## 4．Filter的配置 ##

### url-pattern配置时 ###

1）完全匹配 /sertvle1  
2）目录匹配 /aaa/bbb/\* ----最多的  
/user/*：访问前台的资源进入此过滤器  
/admin/*：访问后台的资源时执行此过滤器  
3）扩展名匹配 \*.abc \*.jsp

注意：url-pattern可以使用servlet-name替代，也可以混用

### dispatcher：访问的方式(了解) ###

REQUEST：默认值，代表直接访问某个资源时执行filter  
FORWARD：转发时才执行filter  
INCLUDE: 包含资源时执行filter  
ERROR：发生错误时 进行跳转是执行filter  
当web.xml这样的时候：  
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1、第一种情况下  
![在这里插入图片描述][20190325215445387.png]  
![在这里插入图片描述][20190325215435768.png]  
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2、第二种情况下  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 9]  
![在这里插入图片描述][20190325215842785.png]  
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转发  
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浏览器的请求发送给组件1，组件1经过一些处理之后，将request和response对象“传递”给组件2，由组件2继续处理，然后输出响应（当然，也可以继续向其他组件“传递”），这个传递的过程称之为“转发”。整个过程只涉及一次浏览器和服务器之间的“请求-响应”，转发过程中的组件共享同一个请求(request)和响应(response)对象。

3、第二种情况下  
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重定向  
浏览器向某组件发出请求信息，组件向浏览器发回一个重定向响应信息，该响应信息不包含具体的数据内容，只是在响应头信息中包含了需要重定向到的地址信息，该地址可以是任何有效的URL。浏览器收到该重定向响应后会自动的向响应信息头中所指示的地址发出请求。整个重定向的过程涉及[两次“请求-响应”][-]。  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 14]  
当web.xml这样时候  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 15]  
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![在这里插入图片描述][20190325220806783.png]  
总结Filter的作用？  
1）公共代码的提取  
2）可以对request和response中的方法进行增强(**装饰者模式/动态代理**)  
3）进行权限控制

## 登录的基本实现 ##

com.itcast.web.servlet.LoginServlet

package com.itcast.web.servlet;
    
    import java.io.IOException;
    import java.sql.SQLException;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    
    import com.itcast.domain.User;
    import com.itcast.service.UserService;
    
    public class LoginServlet extends HttpServlet {
    
    	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		//数据产生之后显示给用户了，等会还要使用的情况下使用Httpsession域
    		HttpSession session = request.getSession();
    		
    		//获取数据
    		String username = request.getParameter("username");//
    		String password = request.getParameter("password");
    		
    		UserService service = new UserService();
    		User user = null;
    		try {
    			user = service.login(username,password);
    		} catch (SQLException e) {
    			e.printStackTrace();
    		}
    		if(user != null){
    			//登录成功
    			//将登录的用户的user对象存到session中
    			//后续界面可能会用到user对象
    			session.setAttribute("user", user);
    			//重定向到首页
    			response.sendRedirect(request.getContextPath());
    		}else{
    			//失败,转发到登录界面 显示提示信息
    			request.setAttribute("loginInfo", "用户名或密码错误");
    			//将数据域转发到login.jsp
    			request.getRequestDispatcher("/login.jsp").forward(request, response);
    		}
    	}
    
    	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		doGet(request, response);
    	}
    }

com.itcast.service.UserService

package com.itcast.service;
    
    import java.sql.SQLException;
    
    import com.itcast.dao.UserDao;
    import com.itcast.domain.User;
    
    public class UserService {
    
    	public User login(String username, String password) throws SQLException {
    		UserDao dao = new UserDao();
    		return dao.login(username,password);
    	}
    	
    }

com.itcast.dao.UserDao

package com.itcast.dao;
    
    import java.sql.SQLException;
    
    import org.apache.commons.dbutils.QueryRunner;
    import org.apache.commons.dbutils.handlers.BeanHandler;
    import org.apache.commons.dbutils.handlers.BeanListHandler;
    
    import com.itcast.domain.User;
    import com.itcast.utils.DataSourceUtils;
    
    public class UserDao {
    
    	public User login(String username, String password) throws SQLException {
    		QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());
    		String sql = "select * from user where username=? and password=?";
    		return runner.query(sql, new BeanHandler<User>(User.class),username,password);
    	}
    	
    }

webb.xml  
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## 四、案例：自动登录 ##

首先是正常的登录，检查是否勾选了自动登录：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 24]  
1 login.jsp代码

<label> <input type="checkbox" name="autoLogin" value="autoLogin"> 自动登录
    									</label>      <label> <input
    										type="checkbox"> 记住用户名
    									</label>

2 web层LoginServlet

package com.itcast.web.servlet;
    
    import java.io.IOException;
    import java.sql.SQLException;
    
    import javax.servlet.ServletException;
    import javax.servlet.http.Cookie;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    
    import com.itcast.domain.User;
    import com.itcast.service.UserService;
    
    public class LoginServlet extends HttpServlet {
    
    	public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		//数据产生之后显示给用户了，等会还要使用的情况下使用Httpsession域
    		HttpSession session = request.getSession();
    		
    		//获取数据
    		String username = request.getParameter("username");//
    		String password = request.getParameter("password");
    		
    		UserService service = new UserService();
    		User user = null;
    		try {
    			user = service.login(username,password);
    		} catch (SQLException e) {
    			e.printStackTrace();
    		}
    		if(user != null){
    			//登录成功
    			//判断用户是否勾选自动登录
    			String autoLogin = request.getParameter("autoLogin");
    			if(autoLogin != null){
    				Cookie cookie_name = new Cookie("cookie_name", user.getUsername());
    				Cookie cookie_password = new Cookie("cookie_password", user.getPassword());
    				//设置cookie的持久化时间
    				cookie_name.setMaxAge(60*60);
    				cookie_password.setMaxAge(60*60);
    				//设置cookie的携带路径
    				cookie_name.setPath(request.getContextPath());
    				cookie_password.setPath(request.getContextPath());
    				//发送cookie
    				response.addCookie(cookie_name);
    				response.addCookie(cookie_password);
    			}
    			//将登录的用户的user对象存到session中
    			//后续界面可能会用到user对象
    			session.setAttribute("user", user);
    			//重定向到首页
    			response.sendRedirect(request.getContextPath());
    		}else{
    			//失败,转发到登录界面 显示提示信息
    			request.setAttribute("loginInfo", "用户名或密码错误");
    			//将数据域转发到login.jsp
    			request.getRequestDispatcher("/login.jsp").forward(request, response);
    		}
    	}
    
    	public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		doGet(request, response);
    	}
    }

3 web层AutoLoginFilter

package com.itcast.web.filter;
    
    import java.io.IOException;
    import java.sql.SQLException;
    
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.FilterConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    import javax.servlet.http.Cookie;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import javax.servlet.http.HttpSession;
    import com.itcast.domain.User;
    import com.itcast.service.UserService;
    
    public class AutoLoginFilter implements Filter{
    
    	@Override
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
    			throws IOException, ServletException {
    		
    		HttpServletRequest req = (HttpServletRequest) request;
    		HttpServletResponse resp = (HttpServletResponse) response;
    		HttpSession session = req.getSession();
    		//定义cookie_username
    		String cookie_username = null;
    		//定义cookie_password
    		String cookie_password = null;
    		//获得cookie中用户名和密码进行登录的操作
    		//获得cookie
    		Cookie[] cookies = req.getCookies();
    		if(cookies != null){
    			for (Cookie cookie : cookies) {
    				//获得名字是cookie_name和cookie_password
    				if("cookie_name".equals(cookie.getName())){
    					String cookie_name = cookie.getValue();
    				}
    				if("cookie_password".equals(cookie.getName())){
    					cookie_password = cookie.getValue();
    				}				
    			}
    		}
    		
    		//判断username和password是否是null
    		if(cookie_username != null && cookie_password != null){
    			//登录的代码
    			UserService service = new UserService();
    			User user = null;
    			try {
    				user = service.login(cookie_username,cookie_password);
    			} catch (SQLException e) {
    				e.printStackTrace();
    			}
    			//将登录的用户的user对象存到session中
    			session.setAttribute("user", user);
    		}
    		
    		//放行
    		chain.doFilter(req, resp);
    	}
    	@Override
    	public void init(FilterConfig filterConfig) throws ServletException {
    	}
    
    
    	@Override
    	public void destroy() {
    	}
    	
    }

4 service层LoginService

5 dao层LoginDao

package com.itcast.dao;
    
    import java.sql.SQLException;
    
    import org.apache.commons.dbutils.QueryRunner;
    import org.apache.commons.dbutils.handlers.BeanHandler;
    
    
    import com.itcast.domain.User;
    import com.itcast.utils.DataSourceUtils;
    
    public class UserDao {
    
    	public User login(String username, String password) throws SQLException {
    		QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());
    		String sql = "select * from user where username=? and password=?";
    		return runner.query(sql, new BeanHandler<User>(User.class),username,password);
    	}
    	
    }

6 filter配置文件

<filter>
        <filter-name>AutoLoginFilter</filter-name>
        <filter-class>com.itcast.web.filter.AutoLoginFilter</filter-class>
      </filter>
      <filter-mapping>
        <filter-name>AutoLoginFilter</filter-name>
        <url-pattern>/*</url-pattern>
      </filter-mapping>

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 25]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 26]  
再开个网页，发现已经登录成功  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 27]

## 解决全局的乱码 ##

![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 28]  
解决保存Cookie中带有中文会报错问题  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 29]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 30]  
一般来说用Cookie来保存信息的时候是不能带有中文的，但是有时候必须要用到中文的时候该怎么办呢？

看下面的例子：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 31]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 32]  
再次访问：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 33]  
解决方法：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 34]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 35]  
案例：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 36]  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3dlaXhpbl80MDgwNzI0Nw_size_16_color_FFFFFF_t_70 37]  
encoding.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    </head>
    <body>
    	<form action="/WEB24/encodingServlet" method="get">
    		<input type="text" name="username">
    		<input type="submit" value="提交">
    	</form>
    </body>
    </html>

com.itcast.web.filter.EncodingFilter

package com.itcast.web.filter;
    
    import java.io.IOException;
    import java.io.UnsupportedEncodingException;
    
    import javax.servlet.Filter;
    import javax.servlet.FilterChain;
    import javax.servlet.FilterConfig;
    import javax.servlet.ServletException;
    import javax.servlet.ServletRequest;
    import javax.servlet.ServletResponse;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletRequestWrapper;
    
    public class EncodingFilter implements Filter{
    
    	
    	@Override
    	public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
    			throws IOException, ServletException {
    		
    		//request.setCharacterEncoding("UTF-8");
    		
    		//在传递request之前对request的getParameter方法进行增强
    		/*
    		 * 装饰者模式(包装)
    		 * 
    		 * 1、增强类与被增强的类要实现统一接口
    		 * 2、在增强类中传入被增强的类
    		 * 3、需要增强的方法重写 不需要增强的方法调用被增强对象的
    		 * 
    		 */
    		
    		//被增强的对象
    		HttpServletRequest req = (HttpServletRequest) request;
    		//增强对象
    		EnhanceRequest enhanceRequest = new EnhanceRequest(req);
    		
    		
    		chain.doFilter(enhanceRequest, response);
    		
    	}
    
    	@Override
    	public void destroy() {
    		
    	}
    	
    	@Override
    	public void init(FilterConfig filterConfig) throws ServletException {
    		
    	}
    
    }
    /*
     * 装饰者模式(包装)
     * 
     * 1、增强类与被增强的类要实现统一接口
     * 2、在增强类中传入被增强的类
     * 3、需要增强的方法重写 不需要增强的方法调用被增强对象的
     * 
     */
    class EnhanceRequest extends HttpServletRequestWrapper{
    	
    	private HttpServletRequest request;
    
    	public EnhanceRequest(HttpServletRequest request) {
    		super(request);
    		this.request = request;
    	}
    	
    	//对getParaameter增强
    	@Override
    	public String getParameter(String name) {
    		String parameter = request.getParameter(name);//乱码
    		try {
    			parameter = new String(parameter.getBytes("iso8859-1"),"UTF-8");
    		} catch (UnsupportedEncodingException e) {
    			e.printStackTrace();
    		}
    		return parameter;
    	}
    	
    }

com.itcast.web.servlet.EncodingServlet

package com.itcast.web.servlet;
    
    import java.io.IOException;
    import javax.servlet.ServletException;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    public class EncodingServlet extends HttpServlet {
    
    	protected void doGet(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
    		
    		String parameter = request.getParameter("username");//中文
    		
    		System.out.println(parameter);
    		
    	}
    
    	protected void doPost(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
    		doGet(request, response);
    	}
    }

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[20190325215445387.png]: /images/20220228/a33dedbbb7714a0fa9af36efda099f48.png
[20190325215435768.png]: /images/20220228/c4b2f6719e4a49b2a9682a22eba1cb1d.png
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[20190325215842785.png]: /images/20220228/435b6467d0384fffb188c74967ca4019.png
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[-]: https://blog.csdn.net/qq_38122518/article/details/80429722
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[20190325220806783.png]: /images/20220228/34629478823b40028ba96900c2b43b50.png
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