Java文件上传接口

1. Java单文件上传接口

import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.UUID;

/**
 * @description:
 * @create: 2019-08-22 11:00
 **/
public class FileUploadUtil {

    /**
     * 上传文件工具类
     * @param uploadFile 文件
     * @param fileDir 文件目录名
     * @param request
     * @return
     */
    public static Msg uploadUtil(MultipartFile uploadFile,String fileDir, HttpServletRequest request) {
        SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd");
        String realPath = request.getSession().getServletContext().getRealPath("/upload/" + fileDir+"/");
        System.out.println("文件上传："+realPath);
        String format = sdf.format(new Date());
        File folder = new File(realPath + format);
        //是否目录
        if (!folder.isDirectory()) {
            folder.mkdirs();
        }
        String filePath = "";

        String oldName = uploadFile.getOriginalFilename();
        String newName = UUID.randomUUID().toString() + oldName.substring(oldName.lastIndexOf("."), oldName.length());
        try {
            //用于图片上传时，把内存中图片写入磁盘
            uploadFile.transferTo(new File(folder, newName));
            filePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + "/upload/" +fileDir+"/" + format +"/"+ newName;
            Msg msg = Msg.success();
            msg.add("path",filePath);
            return msg;
        } catch (Exception e) {
            e.printStackTrace();
        }

        return Msg.fail();
    }
}

2. Java多文件上传接口

import com.newtouch.dangjian.baseapi.util.Info;
import com.newtouch.dangjian.party.service.DeptService;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.persistence.criteria.Predicate;
import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.io.IOException;
import java.text.SimpleDateFormat;
import java.util.*;

/**
 * @Description
 * @Author lph
 * @Date 2020-05-03
 * @Version V1.0
 **/
@RestController
@RequestMapping(path = "upfile")
@Slf4j
public class FileUpLoadController {

    SimpleDateFormat sdf = new SimpleDateFormat("yyyy/MM/dd/");

    @PostMapping("/uploads")
    public String upload(MultipartFile[] uploadFiles, HttpServletRequest request) {
        List list = new ArrayList();//存储生成的访问路径
        if (uploadFiles.length > 0) {
            for (int i = 0; i < uploadFiles.length; i++) {
                MultipartFile uploadFile = uploadFiles[i];
                //设置上传文件的位置在该项目目录下的uploadFile文件夹下，并根据上传的文件日期，进行分类保存
                String realPath = request.getSession().getServletContext().getRealPath("uploadFile");
                String format = sdf.format(new Date());
                File folder = new File(realPath + format);
                if (!folder.isDirectory()) {
                    folder.mkdirs();
                }

                String oldName = uploadFile.getOriginalFilename();
                System.out.println("oldName = " + oldName);
                String newName = UUID.randomUUID().toString() + oldName.
                        substring(oldName.lastIndexOf("."), oldName.length());
                System.out.println("newName = " + newName);
                try {
                    //保存文件
                    uploadFile.transferTo(new File(folder, newName));

                    //生成上传文件的访问路径
                    String filePath = request.getScheme() + "://" + request.getServerName() + ":"+ request.getServerPort() + "/uploadFile" + format + newName;
                    list.add(filePath);
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }
            return list.toString();
        } else if (uploadFiles.length == 0) {
            return "请选择文件8";
        }
        return "上传失败";
    }
    
}

单文件上传接口是本人及同事所写，多文件上传接口的作者是@Author lph

实现文件上传的时候，可以这样做，文件上传单独做成一个接口，返回值是文件路径。然后普通表单做一个接口，文件上传成功后，将文件接口成功返回的路径放到普通表单中，字段是hidden的input。这样提交到普通接口的时候，普通表单字段和文件路径就可以一并写入到数据库中了。

注：第一段亲测有效，可以将入参改为数组类型，这样就变成了多文件上传，那个Msg是自定义的通用返回类；第二段是朋友写的，小伙伴们可以测试一下，本人还未测试。