HttpClient上传文件

1、上传客户端代码：

public static void upload() {  
        CloseableHttpClient httpclient = HttpClients.createDefault();  
        try {  
            HttpPost httppost = new HttpPost("http://172.18.5.107:90/Download.html");  
            FileBody bin = new FileBody(new File("D:\BaiduNetdiskDownload\背景圖\b.jpg")); 
            FileBody bin2 = new FileBody(new File("D:\BaiduNetdiskDownload\背景圖\哈哈哈.jpg")); 
            
            ContentType contentType = ContentType.create("text/plain", Charset.forName("UTF-8"));    
            StringBody comment = new StringBody("123哈哈哈45", contentType);
            MultipartEntityBuilder builder=MultipartEntityBuilder.create();
            
            builder.setCharset(Charset.forName("UTF-8"));//设置请求的编码格式  
            builder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);//设置浏览器兼容模式 
            
            //文件流参数
            builder.addPart("bin",bin);
            builder.addPart("bi哈哈n2",bin2);
            //普通的参数
            builder.addPart("employee_no",comment);
            HttpEntity reqEntity= builder.build();
            httppost.setEntity(reqEntity);  
            System.out.println("executing request " + httppost.getRequestLine());  
            CloseableHttpResponse response = httpclient.execute(httppost);  
            try {  
                System.out.println(response.getStatusLine());  
                HttpEntity resEntity = response.getEntity();  
                if (resEntity != null) {  
                    System.out.println("Response content length: " + resEntity.getContentLength());  
                    System.out.println("Response content: " + EntityUtils.toString(resEntity,"UTF-8"));  
                }  
            } finally {  
                response.close();  
            }  
        } catch (Exception e) {  
            e.printStackTrace();  
        } finally {  
            try {  
                httpclient.close();  
            } catch (IOException e) {  
                e.printStackTrace();  
            }  
        }  
    }  

2、后台下载代码，原生servlet

protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        PrintWriter out = null;  
        //跨越访问
        response.setHeader("Access-Control-Allow-Origin", "*");
        response.setHeader("Access-Control-Allow-Methods", "*");
        response.setHeader("Access-Control-Allow-Headers", "x-requested-with,content-type");         
        response.setCharacterEncoding("utf-8");
        response.setContentType("text/html;charset=UTF-8");  

        FileItemFactory factory = new DiskFileItemFactory();  
        ServletFileUpload upload = new ServletFileUpload(factory);  
        File directory = null;    
        List<FileItem> items = new ArrayList<FileItem>();  
        try {  
            items = upload.parseRequest(request);  
            // 得到所有的文件  
            Iterator<FileItem> it = items.iterator();  
            while (it.hasNext()) {  
                FileItem fItem = (FileItem) it.next();  

                if (fItem.isFormField()) {  
                    // 普通文本框的值 
                    System.out.println(fItem.getFieldName()+fItem.getString("UTF-8"));
                } else { // 获取上传文件的值  
                    String name = fItem.getName();  
                    if(name != null && !("".equals(name))) {  
                        name = name.substring(name.lastIndexOf(File.separator) + 1);  
                        directory = new File("d://test");    
                        directory.mkdirs();  
                        String filePath = ("d://test")+ File.separator + name;  
                        InputStream is = fItem.getInputStream();  
                        FileOutputStream fos = new FileOutputStream(filePath);  
                        byte[] buffer = new byte[1024];  
                        while (is.read(buffer) > 0) {  
                            fos.write(buffer, 0, buffer.length);  
                        }  
                        fos.flush();  
                        fos.close();  
                    }  
                }  
            }  
        } catch (Exception e) {  
            e.printStackTrace();  
        }  
        try {  
            out = response.getWriter();  
            out.print("{success:true, msg:'接收成功'}");  
            out.close();  
        } catch (IOException e) {  
            e.printStackTrace();  
        }  
    }

3、后台下载代码，SpringMVC

public List<String> UploadImage(HttpServletRequest request) {

        List<String> list=new ArrayList<>();
        String employee_no=request.getParameter("employee_no");
        String tmppath=File.separator+"img"+File.separator +employee_no+File.separator;
        String BasePath=request.getRealPath("/")+tmppath;
        String BaseUrl=request.getLocalAddr()+":"+request.getLocalPort()+tmppath;
        System.out.println(BaseUrl);
        try {
            File directory=new File(BasePath);
            if(!directory.exists()){
                directory.mkdirs(); 
            }
            //将当前上下文初始化给  CommonsMutipartResolver （多部分解析器）
            CommonsMultipartResolver multipartResolver=new CommonsMultipartResolver(request.getSession().getServletContext());
            //检查form中是否有enctype="multipart/form-data"
            if(multipartResolver.isMultipart(request))
            {
                //将request变成多部分request
                MultipartHttpServletRequest multiRequest=(MultipartHttpServletRequest)request;
                //获取multiRequest 中所有的文件名
                Iterator iter=multiRequest.getFileNames();
                while(iter.hasNext())
                {
                    //一次遍历所有文件
                    MultipartFile file=multiRequest.getFile(iter.next().toString());
                    if(file!=null)
                    {
                        String name=file.getOriginalFilename();
                        System.out.println(file.getName()+name);
                        String uuid = UUID.randomUUID().toString().replaceAll("-", "").toUpperCase();
                        String ext=name.substring(name.lastIndexOf("."),name.length());
                        String filePath = BasePath+uuid+ext;
                        file.transferTo(new File(filePath));
                        list.add(BaseUrl+uuid+ext);
                    }
                }
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
        return list;
    }