Springboot + MySQL + html 实现文件的上传、存储、下载、删除

实现步骤及效果呈现如下：

1.创建数据库表：

表名：file_test

存储后的数据：

2.创建数据库表对应映射的实体类：

import com.baomidou.mybatisplus.annotation.IdType;
import com.baomidou.mybatisplus.annotation.TableField;
import com.baomidou.mybatisplus.annotation.TableId;
import com.baomidou.mybatisplus.annotation.TableName;
import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;
import java.util.Date;

/**
* 文件实体类
*/
@Data
@AllArgsConstructor
@NoArgsConstructor
@TableName("file_test")
public class File {
    /**
     * 主键id
     */
    @TableId(value = "id",type = IdType.AUTO)
    private Integer id;
    /**
     * 文件名称
     */
    @TableField("file_name")
    private String fileName;
    /**
     * 文件路径
     */
    @TableField("file_path")
    private String filePath;
    /**
     * 上传时间
     */
    @TableField("upload_time")
    private Date uploadTime;
}

创建数据访问层Mapper（用来写数据库的增删改查SQL）

import com.baomidou.mybatisplus.core.mapper.BaseMapper;
import com.fm.model.File;
import org.apache.ibatis.annotations.Mapper;

/**
* 数据库映射
* 集成了mybtis-plus 包含了常用的增删改查方法
*/
@Mapper
public interface FileMapper extends BaseMapper<File> {
}

创建业务层service

import com.baomidou.mybatisplus.extension.service.IService;
import com.fm.model.File;
import org.springframework.web.multipart.MultipartFile;

/**
* 文件业务层
* 集成了mybatis-plus 里面包含了数据库常用的增删改成方法
*/
public interface FileService extends IService<File> {
void upload(MultipartFile file);
}

创建业务实现类serviceImpl

import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
import com.fm.mapper.FileMapper;
import com.fm.model.File;
import com.fm.service.FileService;
import org.springframework.stereotype.Service;
import org.springframework.web.multipart.MultipartFile;
import javax.annotation.Resource;
import java.io.IOException;
import java.util.Date;

/**
* 文件业务实现层
* 集成了mybatis-plus 里面包含了数据库常用的增删改成方法
*/
@Service
public class FileServiceImpl extends ServiceImpl<FileMapper, File> implements FileService {
    @Resource
    private FileMapper fileMapper;

    @Override
    public void upload(MultipartFile file) {
        //获取当前项目所在根目录
        String rootDirectory = System.getProperty("user.dir");
        //如果当前项目根目录不存在（file_manage文件存储）文件夹，
        // 会自动创建该文件夹用于存储项目上传的文件
        java.io.File savaFile = new java.io.File(rootDirectory + "/file_manage项目文件存储/" + file.getOriginalFilename());
        if (!savaFile.getParentFile().exists()) {
            savaFile.getParentFile().mkdirs();
        }
        //如果当前名称的文件已存在则跳过
        if (savaFile.exists()) {
            return;
        }
        try {
            savaFile.createNewFile();
            file.transferTo(savaFile);
        } catch (IOException e) {
            e.printStackTrace();
        }
        File file1 = new File();
        file1.setFileName(file.getOriginalFilename());
        file1.setFilePath("/file_manage项目文件存储/" + file.getOriginalFilename());
        file1.setUploadTime(new Date());
        fileMapper.insert(file1);
    }
}

创建接口层controller(用来写上传、下载、查询列表、删除接口)

import com.fm.model.File;
import com.fm.service.FileService;
import com.fm.util.FileUtil;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;

import javax.annotation.Resource;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.util.List;

/**
* 文件接口层
*/
@CrossOrigin
@RestController
@RequestMapping("/file")
public class FileController {

    //文件实现层
    @Resource
    private FileService fileService;

    /**
     * 文件列表
     */
    @RequestMapping(value = "/list", method = RequestMethod.GET)
    public List<File> list(
    ) {
        try {
            List<File> list = fileService.list();
            return list;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 上传文件
     *
     * @param file
     * @return
     */
    @RequestMapping(value = "/upload", method = RequestMethod.POST)
    public String upload(
            @RequestParam(value = "file") MultipartFile file//文件
    ) {
        try {
            fileService.upload(file);
            return "文件上传成功！";
        } catch (Exception e) {
            e.printStackTrace();
            return "文件上传失败！";
        }
    }

    /**
     * 删除文件
     *
     * @param fileId
     * @return
     */
    @RequestMapping(value = "/delete", method = RequestMethod.DELETE)
    public String delete(
            @RequestParam(value = "fileId") String fileId//文件
    ) {
        try {
            File file = fileService.getById(fileId);
            //获取当前项目所在根目录
            String rootDirectory = System.getProperty("user.dir");
            java.io.File savaFile = new java.io.File(rootDirectory + file.getFilePath());
            //删除保存的文件
            savaFile.delete();
            boolean b = fileService.removeById(fileId);
            if (b){
                return "成功！";
            }
            return "失败！";
        } catch (Exception e) {
            e.printStackTrace();
            return "失败";
        }
    }

    /**
     * 下载文件
     */
    @RequestMapping(value = "/download", method = RequestMethod.GET)
    public void download(@RequestParam(value = "fileId") String fileId,
                         HttpServletResponse response, HttpServletRequest request
    ) {
        try {
            File file = fileService.getById(fileId);
            if (file != null) {
                //获取当前项目所在根目录
                String rootDirectory = System.getProperty("user.dir");
                //调用自主实现的下载文件工具类中下载文件的方法
                FileUtil.doDownloadFile(rootDirectory + file.getFilePath(), response, request);
            }
        } catch (Exception e) {
            e.printStackTrace();
            System.out.println("下载文件出错,错误原因:" + e);
        }
    }
}

文件工具类（用来写下载文件的方法）

/**
* 文件工具类
*/
public class FileUtil {

    /**
     * 下载文件
     * @param Path
     * @param response
     * @param request
     */
    public static void doDownloadFile(String Path, HttpServletResponse response, HttpServletRequest request) {
        try {
            //关键点，需要获取的文件所在文件系统的目录，定位准确才可以顺利下载文件
            String filePath = Path;
            File file = new File(filePath);
            //创建一个输入流，将读取到的文件保存到输入流
            InputStream fis = new BufferedInputStream(new FileInputStream(filePath));
            byte[] buffer = new byte[fis.available()];
            fis.read(buffer);
            fis.close();
            // 清空response
            response.reset();
            // 重要，设置response的Header
            response.setHeader("Content-Disposition", "attachment;filename=" + new String(file.getName().getBytes()));
            response.setHeader("Content-Length", "" + file.length());
            //octet-stream是二进制流传输，当不知文件类型时都可以用此属性
            response.setContentType("application/octet-stream");
            //跨域请求，*代表允许全部类型
            response.setHeader("Access-Control-Allow-Origin", "*");
            //允许请求方式
            response.setHeader("Access-Control-Allow-Methods", "POST, GET, OPTIONS, DELETE");
            //用来指定本次预检请求的有效期，单位为秒，在此期间不用发出另一条预检请求
            response.setHeader("Access-Control-Max-Age", "3600");
            //请求包含的字段内容，如有多个可用哪个逗号分隔如下
            response.setHeader("Access-Control-Allow-Headers", "content-type,x-requested-with,Authorization, x-ui-request,lang");
            //访问控制允许凭据，true为允许
            response.setHeader("Access-Control-Allow-Credentials", "true");
            //创建一个输出流，用于输出文件
            OutputStream oStream = new BufferedOutputStream(response.getOutputStream());
            //写入输出文件
            oStream.write(buffer);
            oStream.flush();
            oStream.close();
        } catch (Exception e) {
            System.out.println("下载日志文件出错,错误原因:" + e);
        }
    }
}

Pom文件依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>
    <parent>
        <groupId>org.springframework.boot</groupId>
        <artifactId>spring-boot-starter-parent</artifactId>
        <version>2.3.12.RELEASE</version>
        <relativePath/> 
    </parent>
    <groupId>com.fm</groupId>
    <artifactId>file_manage</artifactId>
    <version>0.0.1-SNAPSHOT</version>
    <name>file_manage</name>
    <description>file_manage</description>
    <properties>
        <java.version>22</java.version>
    </properties>
    <dependencies>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-web</artifactId>
        </dependency>

        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <optional>true</optional>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>


        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>8.0.29</version>
        </dependency>

        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-jdbc</artifactId>
        </dependency>

        <dependency>
            <groupId>com.baomidou</groupId>
            <artifactId>mybatis-plus-boot-starter</artifactId>
            <version>3.5.1</version>
        </dependency>


        <dependency>
            <groupId>com.alibaba</groupId>
            <artifactId>fastjson</artifactId>
            <version>1.2.70</version>
        </dependency>

    </dependencies>

    <build>
        <plugins>
            <plugin>
                <groupId>org.springframework.boot</groupId>
                <artifactId>spring-boot-maven-plugin</artifactId>
                <configuration>
                    <excludes>
                        <exclude>
                            <groupId>org.projectlombok</groupId>
                            <artifactId>lombok</artifactId>
                        </exclude>
                    </excludes>
                </configuration>
            </plugin>
        </plugins>
    </build>

</project>

yml配置文件：

#数据库连接配置
spring:
  datasource:
    driver-class-name: com.mysql.cj.jdbc.Driver
    url: jdbc:mysql://localhost:3306/file_test?useUnicode=true&characterEncoding=utf-8&allowMultiQueries=true&useSSL=false
    username: root
    password:

  jackson:
    date-format: yyyy-MM-dd HH:mm:ss
    #    joda-date-time-format: yyyy-MM-dd HH:mm:ss
    time-zone: GMT+8

  thymeleaf:
    prefix: classpath:/static
    suffix: .html
    cache: false

#启动端口
server:
  port: 8100

Html前端静态页面（内置在springboot项目中可直接运行）：

<!DOCTYPE html>
<head>
    <meta charset="UTF-8">
</head>
<html lang="en">
<body>
<div id="app">
    <div class="container-fluid">
        
        <div class="row">
            <div align="center" class="col-sm-6 col-sm-offset-3"><button style="font-size: 18px;float: right" href="" class="btn btn-info btn-sm" @click.prevent="uploadFile()">上传文件</button><h1 class="text-center">文件列表</h1></div>
        </div>
        
        <div class="row">
            <div class="col-sm-10 col-sm-offset-1">
                
                <table class="table table-striped table-bordered" style="margin-top: 10px;">
                    <tr>
                        <td align="center" style="font-size: 18px;">文件名称</td>
                        <td align="center" style="font-size: 18px;">文件路径</td>
                        <td align="center" style="font-size: 18px;">上传时间</td>
                        <td align="center" style="font-size: 18px;">操作</td>
                    </tr>
                    <tr v-for="user in list">
                        <td style="font-size: 18px;">{{user.fileName}}</td>
                        <td style="font-size: 18px;">{{user.filePath}}</td>
                        <td style="font-size: 18px;">{{user.uploadTime}}</td>
                        <td>
                            <button style="font-size: 18px;" href=" " class="btn btn-info btn-sm" @click="deleteFile(user.id)">删除</button>
                            <a style="font-size: 18px;" href=" " class="btn btn-info btn-sm" @click="downloadFile(user.id)">下载</a>
                        </td>
                    </tr>
                </table>
            </div>
        </div>
    </div>
</div>


<div id="my_dialog" class="my-dialog" style="display: none">
    <h3>需要上传的文件</h3>
    <form id="form1" action="http://localhost:8100/file/upload" target="form1" method="post" enctype="multipart/form-data">
        <input type="file" name="file" accept=".jpg,.png,.gif">
        <button type="button" style="font-size: 18px;" onclick="upload()">提交</button>
        <button type="button" style="font-size: 18px;" onclick="cancelFile()">取消</button>
    </form>
</div>

<style type="text/css">
    .container-fluid {
        width: 650px;
    //height: 200px;
    //background-color: orchid;
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        margin: auto;
    }

    .my-dialog {
        width: 300px;
    //height: 200px;
    //background-color: orchid;
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        margin: auto;
    }

</style>

</body>
</html>

<script type="text/javascript" src="js/jquery-1.9.1.min.js"></script>

<script src="js/axios.min.js"></script>

<script src="js/vue.js"></script>
<script>
    var app = new Vue({
        el: "#app",
        data:{
            msg:"vue 生命周期",
            list:[], //定义一个list空数组，用来存贮所有文件的信息
        },
        methods:{
            uploadFile(){ //文件选择
                /*悬浮窗口的显示,需要将display变成block*/
                document.getElementById("my_dialog").style.display = "block";
                /*将列表隐藏*/
                document.getElementById("app").style.display = "none";
            },

            deleteFile(id){
                /*alert("删除！");*/
                console.log("打印数据"+id);

                axios.delete('http://localhost:8100/file/delete',{
                    params:{
                        fileId:id,
                    },
                }).then(response=>{

                    console.log("回调--->>>"+response.data);

                    if (response.data == "成功！") {
                        alert("删除成功！");
                        //跳转到显示页面
                        //document.referrer 前一个页面的URL 返回并刷新页面
                        location.replace(document.referrer);
                    } else {
                        alert("删除失败！");
                        //document.referrer 前一个页面的URL 返回并刷新页面
                        location.replace(document.referrer);
                    }
                })
            },

            downloadFile(id){
                window.open("http://localhost:8100/file/download?fileId="+id);

            },

        },
        computed:{

        },
        created(){ //执行 data methods computed 等完成注入和校验
            //发送axios请求
            axios.get("http://localhost:8100/file/list").then(res=>{
                console.log(res.data);
                this.list = res.data;
            }); //es6 箭头函数注意：箭头函数内部没有自己this 简化 function(){} //存在自己this
        },
    });

    cancelFile=function(){ //返回首页
        /*浮窗口隐藏*/
        document.getElementById("my_dialog").style.display = "none";
        /*将列表显示*/
        document.getElementById("app").style.display = "block";

    };

    function upload() {
        /*alert('文件上传成功！');*/
        $("#form1").submit();

        //document.referrer 前一个页面的URL 返回并刷新页面
        location.replace(document.referrer);

    }
</script>