示例环境:JDK8+MAVEN3+SSM(Spring+SpringMVC+MyBatis Plus或者MyBatis)
现在比较流行的除了分布式或微服务就是动静分离。
动静分离，以nginx集群为例，nginx通常加载静态资源(js,img,css等）效率相对tomcat等应用服务器效率是非常高的，由其专门处理静态资源，而动态资源，通常由tomcat等应用服务器来处理，应用服务器处理动态资源的效率比nginx处理静态资源效率又要高很多很多。就将它们做一个分工。利于静态资源处理就使用nginx，利于动态资源处理使用tomcat或者其他应用服务器等。这样分离的好处，各自发挥其优势，即利于资源充分利用，又利于系统性能。
传统的图片服务器ftp，就现在而言已经没几个人在用了，当然了，wordpress相关的插件安装和主题下载就用到ftp。
当然了，还有不少企业将上传文件(包含图片等)放入线上tomcat某个文件夹下或者项目里面，这样的弊端使项目会越来越庞大，之前庞大是因为不断增长的需求，代码不得不越多，因此也会扩充容量。
不过目前很多企业通常采用比如腾讯云、阿里云、七牛云等对象存储，作为图片存储。
一、导入依赖
<!-- 腾讯云 --><dependency> ??????????<groupId>com.qcloud</groupId> ??????????<artifactId>cos_api</artifactId> ??????????<version>5.2.4</version></dependency>
二、编写工具类
package com.custome;import com.qcloud.cos.COSClient; ?import com.qcloud.cos.ClientConfig; ?import com.qcloud.cos.auth.BasicCOSCredentials; ?import com.qcloud.cos.auth.COSCredentials; ?import com.qcloud.cos.model.ObjectMetadata; ?import com.qcloud.cos.model.PutObjectResult; ?import com.qcloud.cos.region.Region; ?import org.springframework.web.multipart.MultipartFile; ?import java.io.*; ?import java.net.URL; ?import java.util.Date; ?import java.util.Random; public class COSClientUtil { ???????//todo 这些变量信息自行到 腾讯云对象存储控制台 获取 ??????private COSClient cOSClient; ???????private static final String ENDPOINT = "test.com"; ?//用户可以指定域名，不指定则为默认生成的域名 ???????//secretId ??????private static final String secretId = "AKIDCJ"; ???// secretKey ????private static final String secretKey = "CD7"; ???// 存储通名称 ???????private static final String bucketName = "test";//公有读私有写// 1 初始化用户身份信息(secretId, secretKey) ?????private static COSCredentials cred = new BasicCOSCredentials(secretId, secretKey); ???// 2 设置bucket的区域, COS地域的简称请参照 https://cloud.tencent.com/document/product/436/6224 ?????private static ClientConfig clientConfig = new ClientConfig(new Region("ap-beijing-1")); ???// 3 生成cos客户端 ?????private static COSClient cosclient = new COSClient(cred, clientConfig); ???????public COSClientUtil() { ?????????cOSClient = new COSClient(cred, clientConfig); ?????} ???????/** ?????* 销毁 ?????*/ ?????public void destory() { ?????????cOSClient.shutdown(); ?????} ???????/** ?????* 上传图片 ?????* ?????* @param url ?????*/ ?????public void uploadImg2Cos(String url) throws Exception { ?????????File fileOnServer = new File(url); ?????????FileInputStream fin; ?????????try { ?????????????fin = new FileInputStream(fileOnServer); ?????????????String[] split = url.split("/"); ?????????????this.uploadFile2Cos(fin, split[split.length - 1]); ?????????} catch (FileNotFoundException e) { ?????????????throw new Exception("图片上传失败"); ?????????} ?????} ???????public String uploadFile2Cos(MultipartFile file) throws Exception { ?????????if (file.getSize() > 10 * 1024 * 1024) { ?????????????throw new Exception("上传图片大小不能超过10M！"); ?????????} ?????????//图片名称 ???????String originalFilename = file.getOriginalFilename(); ?????????System.out.println("originalFilename = " + originalFilename); ???????//图片后缀 ???????String substring = originalFilename.substring(originalFilename.lastIndexOf(".")).toLowerCase(); ?????????System.out.println("substring = " + substring); ???????Random random = new Random(); ?????????//生成新的图片名称(随机数0-9999+系统当前时间+上传图片名) ???????String name = random.nextInt(10000) + System.currentTimeMillis() + "_" + substring; ?????????try { ?????????????InputStream inputStream = file.getInputStream(); ?????????????this.uploadFile2Cos(inputStream, name); ?????????????return name; ?????????} catch (Exception e) { ?????????????throw new Exception("图片上传失败"); ?????????} ?????} ???????/** ?????* 获得图片路径 ?????* ?????* @param fileUrl ?????* @return ?????*/ ?????public String getImgUrl(String fileUrl) { ?????????return getUrl(fileUrl); ?????} ???????/** ?????* 获得url链接 ?????* ?????* @param key ?????* @return ?????*/ ?????public String getUrl(String key) { ?????????// 设置URL过期时间为10年 3600l* 1000*24*365*10 ?????????Date expiration = new Date(System.currentTimeMillis() + 3600L * 1000 * 24 * 365 * 10); ?????????// 生成URL ?????????URL url = cOSClient.generatePresignedUrl(bucketName, key, expiration); ?????????if (url != null) { ?????????????return url.toString(); ?????????} ?????????return null; ?????} ???????/** ?????* 上传到COS服务器 如果同名文件会覆盖服务器上的 ?????* ?????* @param instream ?????* ???????????文件流 ?????* @param fileName ?????* ???????????文件名称 包括后缀名 ?????* @return 出错返回"" ,唯一MD5数字签名 ?????*/ ?????public String uploadFile2Cos(InputStream instream, String fileName) { ?????????String ret = ""; ?????????try { ?????????????// 创建上传Object的Metadata ?????????????ObjectMetadata objectMetadata = new ObjectMetadata(); ?????????????objectMetadata.setContentLength(instream.available()); ?????????????objectMetadata.setCacheControl("no-cache"); ?????????????objectMetadata.setHeader("Pragma", "no-cache"); ?????????????objectMetadata.setContentType(getcontentType(fileName.substring(fileName.lastIndexOf(".")))); ?????????????objectMetadata.setContentDisposition("inline;filename=" + fileName); ?????????????// 上传文件 ?????????????PutObjectResult putResult = cOSClient.putObject(bucketName, ?fileName, instream, objectMetadata); ?????????????ret = putResult.getETag(); ?????????} catch (IOException e) { ?????????????e.printStackTrace(); ?????????} finally { ?????????????try { ?????????????????if (instream != null) { ?????????????????????instream.close(); ?????????????????} ?????????????} catch (IOException e) { ?????????????????e.printStackTrace(); ?????????????} ?????????} ?????????return ret; ?????} ???????/** ?????* Description: 判断Cos服务文件上传时文件的contentType ?????* ?????* @param filenameExtension 文件后缀 ?????* @return String ?????*/ ?????public static String getcontentType(String filenameExtension) { ?????????if (filenameExtension.equalsIgnoreCase("bmp")) { ?????????????return "image/bmp"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("gif")) { ?????????????return "image/gif"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("jpeg") || filenameExtension.equalsIgnoreCase("jpg") ?????????????????|| filenameExtension.equalsIgnoreCase("png")) { ?????????????return "image/jpeg"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("html")) { ?????????????return "text/html"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("txt")) { ?????????????return "text/plain"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("vsd")) { ?????????????return "application/vnd.visio"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("pptx") || filenameExtension.equalsIgnoreCase("ppt")) { ?????????????return "application/vnd.ms-powerpoint"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("docx") || filenameExtension.equalsIgnoreCase("doc")) { ?????????????return "application/msword"; ?????????} ?????????if (filenameExtension.equalsIgnoreCase("xml")) { ?????????????return "text/xml"; ?????????} ?????????return "image/jpeg"; ?????} ?????}三、编写Controller方法
???@PostMapping(value="/uploadPicture",produces="application/json;charset=utf-8") ???public JSONObject upModify(HttpServletRequest request, MultipartFile file) { ???????????????JSONObject json = new JSONObject(); ???????try { ???????????????????????COSClientUtil cosClientUtil = new COSClientUtil(); ????????????????????????//获取Cookie ???????????String cookie = CookieUtils.getCookie(request,"userCode"); ???????????????????????//解密后的userCode ???????????String decodeStr = Base64.decodeStr(cookie); ???????????????????????????????????????????if(!file.isEmpty()) { ???????????????????????????????String name = cosClientUtil.uploadFile2Cos(file); ????????????????//图片名称 ???????????????System.out.println("name = " + name); ???????????????//上传到腾讯云 ???????????????String img_url = cosClientUtil.getImgUrl(name); ????????????????System.out.println("img_url = " + img_url); ???????????????????????????????//数据库保存图片地址 ???????????????String db_img_url = img_url.substring(0,img_url.indexOf("?")); ???????????????System.out.println("db_img_url = " + db_img_url); ???????????????????????????????SysUser user = new SysUser(); ???????????????user.setUserCode(decodeStr); ???????????????user.setAvatar(db_img_url); ???????????????????????????????//调用修改逻辑 ???????????????boolean isModifyUser = userService.updateById(user); ???????????????????????????????if(isModifyUser) { ???????????????????????????????????????json.put("returnCode", "000000"); ???????????????????json.put("returnMsg", "上传文件成功"); ???????????????}else { ???????????????????json.put("returnCode", "111111"); ???????????????????json.put("returnMsg", "上传文件失败"); ???????????????????????????????} ???????????}else { ???????????????json.put("returnCode", "222222"); ???????????????json.put("returnMsg", "参数异常"); ???????????} ???????????????????} catch (Exception e) { ???????????e.printStackTrace(); ???????????json.put("returnCode", "333333"); ???????????json.put("returnMsg", "特殊异常"); ???????????} ???????????????return json; ???}四、编写简单html测试
<!DOCTYPE html><html><head><meta charset="UTF-8"><title>上传图片测试</title><script type="text/javascript" src="../js/jquery-1.8.0.min.js"></script><script type="text/javascript">function setImg(obj){//用于进行图片上传，返回地址 ???var f = $(obj).val(); ???if(f == null || f == undefined || f == ‘‘){ ???????return false; ???} ???if(!/\.(?:png|jpg|bmp|gif|PNG|JPG|BMP|GIF)$/.test(f)) ???{ ???????alertLayel("类型必须是图片(.png|jpg|bmp|gif|PNG|JPG|BMP|GIF)"); ???????$(obj).val(‘‘); ???????return false; ???} ???var data = new FormData(); ???$.each($(obj)[0].files,function(i,file){ ???????data.append(‘file‘, file); ???}); ???????var upload_img = $("#uploadinput")[0].files[0]; ???var url = window.URL.createObjectURL(upload_img); ???????$.ajax({ ???????type: "POST", ???????url: "uploadPicture", ???????data: data, ???????cache: false, ???????contentType: false, ????//必须false才会自动加上正确的Content-Type ?????????processData: false, ????//必须false才会自动加上正确的Content-Type ?????????dataType:"json", ???????success: function(data) { ???????????alert(data.returnMsg) ???????????????????}, ???????error: function(XMLHttpRequest, textStatus, errorThrown) { ????????????alert(XMLHttpRequest.status); ????????????// 状态 ????????????alert(XMLHttpRequest.readyState); ????????????// 错误信息 ???????????????alert(textStatus); ???????} ???});}</script></head><body> <input type="file" id="uploadinput" name="file" onchange="setImg(this)"/></body></html>腾讯云图片上传
原文地址：https://www.cnblogs.com/youcong/p/9494895.html