用httpclient4.3 post方式推送文件到服务端  准备：httpclient-4.3.3.jar；httpcore-4.3.2.jar；httpmime-4.3.3.jar/*** 上传文件* @throws  ParseException* @throws  IOException*/
publicstaticvoidpostFile()throwsParseException, IOException{CloseableHttpClient httpClient = HttpClients.createDefault();try{// 要上传的文件的路径String filePath =newString("F:/pic/001.jpg");// 把一个普通参数和文件上传给下面这个地址 是一个servletHttpPost httpPost =newHttpPost("http://localhost:8080/xxx/xxx.action");// 把文件转换成流对象FileBodyFile file =newFile(filePath);FileBody bin =newFileBody(file); StringBody uploadFileName =newStringBody("把我修改成文件名称", ContentType.create("text/plain", Consts.UTF_8));//以浏览器兼容模式运行，防止文件名乱码。 HttpEntity reqEntity = MultipartEntityBuilder.create().setMode(HttpMultipartMode.BROWSER_COMPATIBLE).addPart("uploadFile", bin)//uploadFile对应服务端类的同名属性<File类型>.addPart("uploadFileName", uploadFileName)//uploadFileName对应服务端类的同名属性<String类型>.setCharset(CharsetUtils.get("UTF-8")).build();httpPost.setEntity(reqEntity);System.out.println("发起请求的页面地址 "+ httpPost.getRequestLine());// 发起请求 并返回请求的响应CloseableHttpResponse response = httpClient.execute(httpPost);try{System.out.println("----------------------------------------");// 打印响应状态
            System.out.println(response.getStatusLine());// 获取响应对象HttpEntity resEntity = response.getEntity();if(resEntity !=null) {// 打印响应长度System.out.println("Response content length: "+ resEntity.getContentLength());// 打印响应内容
                System.out.println(EntityUtils.toString(resEntity,Charset.forName("UTF-8")));}// 销毁
            EntityUtils.consume(resEntity);}finally{response.close();}}finally{httpClient.close();}
}/*** 下载文件* @param  url* @param  destFileName   xxx.jpg/xxx.png/xxx.txt* @throws  ClientProtocolException* @throws IOException*/
publicstaticvoidgetFile(String url, String destFileName)throwsClientProtocolException, IOException {// 生成一个httpclient对象CloseableHttpClient httpclient = HttpClients.createDefault();HttpGet httpget =newHttpGet(url);HttpResponse response = httpclient.execute(httpget);HttpEntity entity = response.getEntity();InputStream in = entity.getContent();File file =newFile(destFileName);try{FileOutputStream fout =newFileOutputStream(file);intl = -1;byte[] tmp =newbyte[1024];while((l = in.read(tmp)) != -1) {fout.write(tmp,0, l);// 注意这里如果用OutputStream.write(buff)的话，图片会失真，大家可以试试
        }fout.flush();fout.close();}finally{// 关闭低层流。
        in.close();}httpclient.close();
}