• SpringMVC实现文件的上传（CommonsMultipartResolver和StanderServletMultipartResolver）

         一定要足够优秀才能堵住悠悠众口。

    b14fbd0383c74866b141a8322afde37c.jpg

     

    文件上传功能在SpringMVC中有两种方法（两种不同的处理器）

    2df7c8607da74692b9cbedeb95edd23c.png

     这篇文章我们将通过这两种方法来实现文件上传功能

    1：CommonsMultipartResolver

    创建一个新的Maven项目并在项目中进行基础的环境配置

    Maven项目基础配置，如果不同可以参考一下

    一：在pom.xml中导入我们即将用到的依赖

    1.         <dependency>
    2.             <groupId>commons-fileuploadgroupId>
    3.             <artifactId>commons-fileuploadartifactId>
    4.             <version>1.4version>
    5.         dependency>

    二：创建网页，实现前端出现页面

    注意：这里创建的是动态网页

    1. <%@ page contentType="text/html;charset=UTF-8" language="java" %>
    2. <html>
    3. <head>
    4.     <title>Titletitle>
    5. head>
    6. <body>
    7. <form  action="/play" method="post" enctype="multipart/form-data">
    8.     <input type="file" name="file">
    9.     <input type="submit" value="提交">
    10. form>
    11. body>
    12. html>

    三：创建SpringMVC框架的控制器

    1. package fileupload_demo1;
    2.  
    3. import org.springframework.stereotype.Controller;
    4. import org.springframework.web.bind.annotation.GetMapping;
    5. import org.springframework.web.bind.annotation.RequestMapping;
    6. import org.springframework.web.bind.annotation.ResponseBody;
    7. import org.springframework.web.multipart.MultipartFile;
    8.  
    9. import javax.servlet.http.HttpServletRequest;
    10. import java.io.File;
    11. import java.io.IOException;
    12. import java.text.SimpleDateFormat;
    13. import java.util.Date;
    14. import java.util.UUID;
    15.  
    16. @Controller
    17. public class CT1 {
    18.     SimpleDateFormat simpleDateFormat = new SimpleDateFormat("/yyyy/MM/dd/"); //创建日期，并标注时间显示格式
    19.     @GetMapping("/upload")
    20.     public String play1(){
    21.         return "hh";
    22.     }
    23.     @RequestMapping("/play")
    24.     @ResponseBody
    25.     public String play1(MultipartFile file, HttpServletRequest req) throws IOException {
    26.         String format = simpleDateFormat.format(new Date());  //获取今天的日期
    27.         String realpath = req.getServletContext().getRealPath("/img") +format; //获取Tomcat中的临时储存文件
    28.         File folder = new File(realpath);
    29.         if(!folder.exists()){   //检查目录是否存在
    30.             folder.mkdirs();    //目录不存在进行创建
    31.         }
    32.         String oldname = file.getOriginalFilename(); //得到上传时的文件名
    33.         String name = UUID.randomUUID().toString()+oldname.substring(oldname.lastIndexOf(".")); //UUID.randomUUID().toString()：Java中自动生成主键的方法，机器中生成的一串生成数字
    34.         file.transferTo(new File(folder,name)); //将前端传来的数据保存指定名字保存在指定文件夹下
    35.         String url = req.getScheme()+ "://"+req.getServerName() +":"+req.getServerPort() +"/img" +format +name;
    36.         return url;
    37.  
    38.         //http://localhost:8080/img/2022/11/13/8d3910d1-2a7c-47ce-8251-3cc4eeaf0bc4.jpeg
    39.  
    40.     }
    41.  
    42. }

    注意：下面标注了代码获取的结果

    c7e57f38f15648e2903bf070bce07685.png

     四：配置SpringMVC

    1. "1.0" encoding="UTF-8"?>
    2. <beans xmlns="http://www.springframework.org/schema/beans"
    3.        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    4.        xmlns:context="http://www.springframework.org/schema/context"
    5.        xmlns:mvc="http://www.springframework.org/schema/mvc"
    6.  
    7.        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd">
    8.  
    9.     
    10.     <context:component-scan base-package="fileupload_demo1">context:component-scan>
    11.     <mvc:annotation-driven/>
    13.     <mvc:resources mapping="/**" location="/">mvc:resources>
    15.     <bean class="org.springframework.web.multipart.commons.CommonsMultipartResolver" id="multipartResolver">
    16.      
    17.     <property name="defaultEncoding" value="UTF-8"/>
    18.     
    19.     <property name="maxUploadSize" value="1048576"/>
    20.     
    21.     <property name="maxUploadSizePerFile" value="1048576"/>
    22.     
    23.     <property name="maxInMemorySize" value="4096"/>
    24.     
    25.     <property name="uploadTempDir" value="file:///E:\\tmp"/>   
    26. bean>
    27.  
    28.     
    29.     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="modelAndView">
    30.         <property name="prefix" value="/jsp/">property>
    31.         <property name="suffix" value=".jsp">property>
    32.     bean>
    33.  
    34. beans>

    执行项目：

    前端网页：

    0893f00d25ef4ecb88d7e0833eb3addf.png

     点击提交，返回图片url

    1df96c4c39744615917a806dc7b1bc70.png

     最终结果：

    ba53f451a60543008c13a6551ab9517b.png

     2:StanderServletMultipartResolver(经常被使用）

    这种方法的配置基本上与第一种方法相同，没有很大的区别

    区别一：将SpringMVC的配置文件中文件上传的类进行更换

    1. "1.0" encoding="UTF-8"?>
    2. <beans xmlns="http://www.springframework.org/schema/beans"
    3.        xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    4.        xmlns:context="http://www.springframework.org/schema/context"
    5.        xmlns:mvc="http://www.springframework.org/schema/mvc"
    6.  
    7.        xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/mvc https://www.springframework.org/schema/mvc/spring-mvc.xsd">
    8.  
    9.     
    10.     <context:component-scan base-package="fileupload_demo1">context:component-scan>
    11.     <mvc:annotation-driven/>
    12.     <mvc:resources mapping="/**" location="/">mvc:resources>
    13.     <bean class="org.springframework.web.multipart.support.StandardServletMultipartResolver" id="multipartResolver">bean>
    14.     
    15.     <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="modelAndView">
    16.         <property name="prefix" value="/jsp/">property>
    17.         <property name="suffix" value=".jsp">property>
    18.     bean>
    19.  
    20. beans>

    区别二：将上传文件的参数配置放在web.xml中

    1. "1.0" encoding="UTF-8"?>
    2. <web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
    3.          xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    4.          xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
    5.          version="4.0">
    6.     
    7.         <context-param>
    8.             <param-name>contextConfigLocationparam-name>
    9.             <param-value>classpath:spring.xmlparam-value>
    10.         context-param>
    11.         <listener>
    12.             <listener-class>org.springframework.web.context.ContextLoaderListenerlistener-class>
    13.         listener>
    14.  
    15.     
    16.     <servlet>
    17.         <servlet-name>springmvcservlet-name>
    18.         <servlet-class>org.springframework.web.servlet.DispatcherServletservlet-class>
    19.         <init-param>
    20.             <param-name>contextConfigLocationparam-name>
    21.             <param-value>classpath:SpringMVC.xmlparam-value>
    22.         init-param>
    23.     
    24.         <multipart-config>
    25.             
    27.             
    28.             <max-file-size>1048576max-file-size>
    29.             
    30.             <max-request-size>1048576max-request-size>
    31.             
    32.             <file-size-threshold>4096file-size-threshold>
    33.         multipart-config>
    34.     servlet>
    35.     <servlet-mapping>
    36.         <servlet-name>springmvcservlet-name>
    37.         <url-pattern>/url-pattern>
    38.     servlet-mapping>
    39.     <filter>
    40.         <filter-name>encodingfilter-name>
    41.         <filter-class>org.springframework.web.filter.CharacterEncodingFilterfilter-class>
    42.         <init-param>
    43.             <param-name>encodingparam-name>
    44.             <param-value>UTF-8param-value>
    45.         init-param>
    46.         <init-param>
    47.             <param-name>forceRequestEncodingparam-name>
    48.             <param-value>trueparam-value>
    49.         init-param>
    50.         <init-param>
    51.             <param-name>forceResponseEncodingparam-name>
    52.             <param-value>trueparam-value>
    53.         init-param>
    54.     filter>
    55.     <filter-mapping>
    56.         <filter-name>encodingfilter-name>
    57.         <url-pattern>/*url-pattern>
    58.     filter-mapping>
    59. web-app>

    其他的内容不变实现的功能是相同的结果

     

     

  • 相关阅读:
    Centos系统常见配置（详细）总结
    VoLTE端到端业务详解 | 掉话问题
    秋招求职经验分享
    助力水泥基建裂痕自动化巡检，基于yolov5融合ASPP开发构建多尺度融合目标检测识别系统
    ERR_FAILED 200 解决方案
    数字生活的未来：探索Web3的全新世界
    【k8s源码篇之Informer篇4】关于 Informer 的一些困惑点
    群体优化算法----火山爆发算法介绍以及离散优化Pareto最优解示例
    oracle 数据链接过多，导致后续链接链接不上
    【代码规范】switch 块级的作用域问题
  • 原文地址：https://blog.csdn.net/m0_52479012/article/details/127832868