主要代码部分

package com.zkc.student.controller;import com.zkc.student.utils.DigestUtil;
import org.apache.commons.lang3.StringUtils;
import org.apache.commons.lang3.time.DateFormatUtils;
import org.apache.commons.io.FilenameUtils;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.*;
import org.springframework.web.multipart.MultipartFile;
import java.io.File;
import java.io.IOException;
import java.util.Date;/*** 主要用于图片上传(如果可以看懂，稍加修改就可以文件上传)*/
@Controller
public class ImgUplod {public static final String IMAGE_PNG = "image/png";public static final String IMAGE_JPG = "image/jpg";public static final String IMAGE_JPEG = "image/jpeg";public static final String IMAGE_BMP = "image/bmp";public static final String IMAGE_GIF = "image/gif";/*** 默认的文件名最大长度 100*/public static final int DEFAULT_FILE_NAME_LENGTH = 100;/*** 默认大小 50M*/public static final long DEFAULT_MAX_SIZE = 50 * 1024 * 1024;/**** 允许上传的图片格式** */public static final String[] DEFAULT_ALLOWED_EXTENSION = {// 图片"bmp", "gif", "jpg", "jpeg", "png",// word excel powerpoint"doc", "docx", "xls", "xlsx", "ppt", "pptx", "html", "htm", "txt",// 压缩文件"rar", "zip", "gz", "bz2",// pdf"pdf"};public static final String[] IMAGE_EXTENSION = {"bmp", "gif", "jpg", "jpeg", "png"};public static final String[] FLASH_EXTENSION = {"swf", "flv"};public static final String[] MEDIA_EXTENSION = {"swf", "flv", "mp3", "wav", "wma", "wmv", "mid", "avi", "mpg", "asf", "rm", "rmvb"};private static int counter = 0;@PostMapping("/uplod")@ResponseBodypublic String Uplod(@RequestParam("imgFile") MultipartFile imgFile) throws IOException {if (imgFile.isEmpty()) { //判断是否为空return "请上传图片！";}File fileDir = new File("/student");if (!fileDir.isDirectory()) {   //如果没有 student  文件就创建fileDir.mkdirs();   //创建 student 文件}int ImgFileNamelength = imgFile.getOriginalFilename().length();  //获取名字的长度if (ImgFileNamelength > DEFAULT_FILE_NAME_LENGTH) { //判断图片名字是否超过100return "图片名字长度超过100";}long ImgFileSize = imgFile.getSize();  //获取当前图片大小（字节）if (DEFAULT_MAX_SIZE != -1 && ImgFileSize > DEFAULT_MAX_SIZE) {  //&& 两个条件都成立才行return "图片大小超过50M";}String extension = FilenameUtils.getExtension(imgFile.getOriginalFilename()); //获取文件名的后缀if (StringUtils.isEmpty(extension)) { //判断是否为空 如果为空执行一下操作extension =  Extension(imgFile.getContentType());}String ImgFileName = imgFile.getOriginalFilename();  // 获取图片名字if (DEFAULT_ALLOWED_EXTENSION != null && !isAllowedExtension(extension, DEFAULT_ALLOWED_EXTENSION)) { //判断MIME类型是否是允许的MIME类型 (通俗的解释就是判断当前上传的文件格式是不是允许上传的格式)if (DEFAULT_ALLOWED_EXTENSION == IMAGE_EXTENSION) {return DEFAULT_ALLOWED_EXTENSION + "--------" + extension + "--------" + ImgFileName;} else if (DEFAULT_ALLOWED_EXTENSION == FLASH_EXTENSION) {return DEFAULT_ALLOWED_EXTENSION + "--------" + extension + "--------" + ImgFileName;} else if (DEFAULT_ALLOWED_EXTENSION == MEDIA_EXTENSION) {return DEFAULT_ALLOWED_EXTENSION + "--------" + extension + "--------" + ImgFileName;} else {return DEFAULT_ALLOWED_EXTENSION + "--------" + extension + "--------" + ImgFileName;}}String fileName = "/" + DateFormatUtils.format(new Date(), "yyyy/MM/dd") + "/" + encodingFilename(ImgFileName) + "." + extension; //        /年/月/日/(加密图片名字).(原图片的后缀名)File desc = new File(fileDir.getAbsolutePath() + File.separator + fileName);if (!desc.getParentFile().exists()) {desc.getParentFile().mkdirs();}if (!desc.exists()) {desc.createNewFile();}imgFile.transferTo(desc);String pathFileName = fileDir + fileName;if (StringUtils.contains(fileDir.getAbsolutePath(), ":")) {pathFileName = StringUtils.substringAfterLast(fileDir.getAbsolutePath(), ":") + fileName; // windows 去除盘符}pathFileName = pathFileName.replaceAll("\\\\", "/");  //将 反斜杠（"\"）变成  正斜杠 （"/"）return pathFileName;}/*** 判断MIME类型是否是允许的MIME类型** @param extension* @param allowedExtension* @return*/public static final boolean isAllowedExtension(String extension, String[] allowedExtension) {for (String str : allowedExtension) {if (str.equalsIgnoreCase(extension)) {return true;}}return false;}/*** 编码文件名*/private static final String encodingFilename(String filename) {filename = filename.replace("_", " ");filename = DigestUtil.hmacSign(filename + System.nanoTime() + counter++);return filename;}/**** */public static String Extension(String prefix) {switch (prefix) {case IMAGE_PNG:return "png";case IMAGE_JPG:return "jpg";case IMAGE_JPEG:return "jpeg";case IMAGE_BMP:return "bmp";case IMAGE_GIF:return "gif";default:return "";}}}

图片上床图片路径映射

package com.zkc.student.config;import org.springframework.context.annotation.Configuration;
import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;
import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;/*** 将磁盘文件路径映射为项目访问路径** */
@Configuration
public class WebMvcConfiguration implements WebMvcConfigurer {@Overridepublic void addResourceHandlers(ResourceHandlerRegistry registry) {registry.addResourceHandler("/student/**").addResourceLocations("file:/student/");}
}

对图片名字重命名（用了md5加密的方式）

package com.zkc.student.utils;import java.io.UnsupportedEncodingException;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Arrays;
import java.util.Random;public class DigestUtil {private static String encodingCharset = "UTF-8";public static String hmacSign(String aValue, int length) {String md5Str = hmacSign(aValue);if (md5Str.length() < length) {length = md5Str.length();}return md5Str.substring(0, length);}public static String hmacSign(String aValue) {return hmacSign(aValue, "zkc");}/*** @param aValue* @param aKey* @return*/public static String hmacSign(String aValue, String aKey) {byte k_ipad[] = new byte[64];byte k_opad[] = new byte[64];byte keyb[];byte value[];try {keyb = aKey.getBytes(encodingCharset);value = aValue.getBytes(encodingCharset);} catch (UnsupportedEncodingException e) {keyb = aKey.getBytes();value = aValue.getBytes();}Arrays.fill(k_ipad, keyb.length, 64, (byte) 54);Arrays.fill(k_opad, keyb.length, 64, (byte) 92);for (int i = 0; i < keyb.length; i++) {k_ipad[i] = (byte) (keyb[i] ^ 0x36);k_opad[i] = (byte) (keyb[i] ^ 0x5c);}MessageDigest md = null;try {md = MessageDigest.getInstance("MD5");} catch (NoSuchAlgorithmException e) {return null;}md.update(k_ipad);md.update(value);byte dg[] = md.digest();md.reset();md.update(k_opad);md.update(dg, 0, 16);dg = md.digest();return toHex(dg);}public static int randomCode() {//0550//550//0 - 8999//0+1000  1000//8999   1000  9999return new Random().nextInt(9000) + 1000;}public static String toHex(byte input[]) {if (input == null)return null;StringBuffer output = new StringBuffer(input.length * 2);for (int i = 0; i < input.length; i++) {int current = input[i] & 0xff;if (current < 16)output.append("0");output.append(Integer.toString(current, 16));}return output.toString();}/*** @param args* @param key* @return*/public static String getHmac(String[] args, String key) {if (args == null || args.length == 0) {return (null);}StringBuffer str = new StringBuffer();for (int i = 0; i < args.length; i++) {str.append(args[i]);}return (hmacSign(str.toString(), key));}/*** @param aValue* @return*/public static String digest(String aValue) {aValue = aValue.trim();byte value[];try {value = aValue.getBytes(encodingCharset);} catch (UnsupportedEncodingException e) {value = aValue.getBytes();}MessageDigest md = null;try {md = MessageDigest.getInstance("SHA1");} catch (NoSuchAlgorithmException e) {e.printStackTrace();return null;}return toHex(md.digest(value));}
}

pom.xml

        <!--工具类--><dependency><groupId>org.apache.commons</groupId><artifactId>commons-lang3</artifactId><version>3.7</version></dependency><!-- io常用工具类 --><!-- https://mvnrepository.com/artifact/commons-io/commons-io --><dependency><groupId>commons-io</groupId><artifactId>commons-io</artifactId><version>2.6</version></dependency>

这里只是针对图片上传写的，稍加修改就可以上床其他文件