文件上传下载

import cn.hutool.core.io.FileUtil;
import cn.hutool.core.io.IoUtil;
import lombok.SneakyThrows;
import org.apache.commons.lang3.StringUtils;
import org.apache.poi.ss.usermodel.Workbook;
import org.springframework.http.MediaType;

import javax.servlet.http.HttpServletResponse;
import java.io.*;
import java.nio.charset.StandardCharsets;

public class DownloadUtil {

    /**
     * 下载文件(适用大多数文件类型,如: word,excel,pdf,mp4 等)
     *
     * @param fileName  定义文件名(需带扩展名,如: .docx)
     * @param fileBytes
     * @param response
     */
    public static void downloadFile(String fileName, byte[] fileBytes, HttpServletResponse response) {
        if (StringUtils.isBlank(fileName)) {
            throw new RuntimeException("文件名不能为空");
        }
        String[] split = fileName.split(".");
        if (split.length == 1) {
            throw new RuntimeException("文件名需带扩展名");
        }
        try {
            response.reset();
            response.setHeader("Content-Disposition", "attachment;filename=" + new String(fileName.getBytes(StandardCharsets.UTF_8), StandardCharsets.ISO_8859_1));
            // application/octet-stream: 二进制流传输(适用各种文件类型)
            response.setContentType(MediaType.APPLICATION_OCTET_STREAM_VALUE);
            OutputStream outputStream = new BufferedOutputStream(response.getOutputStream());
            outputStream.write(fileBytes);
            outputStream.flush();
            outputStream.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    public static byte[] file2bytes(File file) {
        return FileUtil.readBytes(file);
    }

    public static byte[] inputStream2bytes(InputStream inputStream, boolean isClose) {
        return IoUtil.readBytes(inputStream, isClose);
    }

    /**
     * 下载 Excel 文件
     *
     * @param fileName
     * @param workbook
     * @param response
     */
    @SneakyThrows
    public static void downloadExcelByWorkbook(String fileName, Workbook workbook, HttpServletResponse response) {
        OutputStream os = null;
        try {
            if (!fileName.contains(".")) {
                fileName = fileName + ".xlsx";
            }
            response.setContentType("application/*");
            response.setHeader("content-disposition", "attachment;filename=" + new String(fileName.getBytes("gb2312"), "ISO8859-1"));
            response.setCharacterEncoding("UTF-8");
            os = response.getOutputStream();
            workbook.write(os);
            os.flush();
        } catch (Exception ignored) {

        } finally {
            os.close();
        }
    }

}

 
import cn.hutool.core.codec.Base64;
import cn.hutool.core.io.IoUtil;
import cn.hutool.http.HttpUtil;
import lombok.SneakyThrows;
import org.apache.commons.io.FileUtils;
import org.junit.Test;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestBody;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.http.HttpServletRequest;
import java.io.File;
import java.util.HashMap;
import java.util.Map;


@RestController
public class UploadFileController {

 

    @SneakyThrows
    @PostMapping(value = "/upload")
    public void uploadMultipartFile(MultipartFile file) {
        File destFile = new File("E:" + File.separator + "upload-test-" + System.currentTimeMillis() + ".xlsx");
        file.transferTo(destFile);
    }

    @SneakyThrows
    @PostMapping(value = "/upload-binary-request")
    public void uploadBinary(HttpServletRequest request) {
        System.err.println(request.getContentType());
        File destFile = new File("E:" + File.separator + "upload-binary-test_" + System.currentTimeMillis() + ".xlsx");
        FileUtils.copyInputStreamToFile(request.getInputStream(), destFile);
    }

    @SneakyThrows
    @PostMapping(value = "/upload-binary-bytes")
    public void uploadBytes(@RequestBody byte[] bytes) {
        File destFile = new File("E:" + File.separator + "upload-bytes-test_" + System.currentTimeMillis() + ".xlsx");
        FileUtils.copyInputStreamToFile(IoUtil.toStream(bytes), destFile);
    }

    @SneakyThrows
    @PostMapping(value = "/upload-base64")
    public void uploadBase64(String base64) {
        File destFile = new File("E:" + File.separator + "upload-string-test_" + System.currentTimeMillis() + ".xlsx");
        Base64.decodeToFile(base64, destFile);
    }

    @Test
    public void testUploadMultipartFile() {
        File file = new File("E:" + File.separator + "test.xlsx");
        Map<String, Object> map = new HashMap<>();
        map.put("file", file);
        HttpUtil.post("http://localhost:8080/upload", map);
    }

    @Test
    public void testUploadBase64() {
        File file = new File("E:" + File.separator + "test.xlsx");
        Map<String, Object> map = new HashMap<>();
        map.put("base64", Base64.encode(file));
        HttpUtil.post("http://localhost:8080/upload-base64", map);
    }

}