依赖jar包:httpclient-4.4.jar、httpcore-4.4.jar、httpmime-4.4.x.jar

/** * httpclient4.x 文件上传 *  * Example how to use multipart/form encoded POST request. */public class ClientMultipartFormPost {     public static void main(String[] args) {        String url = "http://localhost:8080/fileRequest";        File file = new File("/home/opt/fileUpload/A.zip");        CloseableHttpClient httpclient = HttpClients.createDefault();        try {            HttpPost httppost = new HttpPost(url);            MultipartEntityBuilder builder = MultipartEntityBuilder.create();            //others param for request            StringBody stringFileNameBody = new StringBody("fileName", ContentType.create("text/plain", "UTF-8"));            builder.addPart(name, stringFileNameBody);            StringBody stringFileMd5 = new StringBody("md5", ContentType.create("text/plain", "UTF-8"));            builder.addPart(name, stringFileMd5);                         //file param for request            String fileRequestParam = "file";            FileBody fileBody = new FileBody(file, ContentType.create("multipart/form-data", "UTF-8"));            builder.addPart(fileRequestParam, fileBody);                         HttpEntity reqEntity = builder.build();            httppost.setEntity(reqEntity);            System.out.println("executing request " + httppost.getRequestLine());            CloseableHttpResponse response = httpclient.execute(httppost);                      System.out.println(response.getStatusLine());            HttpEntity resEntity = response.getEntity();            if (resEntity != null) {                System.out.println("Response content length: " + resEntity.getContentLength());            }            EntityUtils.consume(resEntity);                   } catch(Exception e){            e.printStackTrace();        }finally {           try {                EntityUtils.consume(resEntity);            } catch (IOException e) {                e.printStackTrace();            }            if (response != null) {                try {                    response.close();                } catch (IOException e) {                    e.printStackTrace();                }            }        }    } }