分享Spring的下载组件

package com.hnust.common.controller; import org.apache.commons.io.FileUtils;import org.springframework.http.HttpHeaders;import org.springframework.http.HttpStatus;import org.springframework.http.MediaType;import org.springframework.http.ResponseEntity;import org.springframework.web.bind.annotation.RestController; import java.io.File;import java.io.IOException;import java.io.UnsupportedEncodingException;import java.net.URLEncoder; /** * Created by Heweipo on 2016/5/27. * <p> * 下载通用控制器 */@RestControllerpublic class DownloadController extends BaseController {   /**   * 下载文件通用方法   *   * @param file 文件对象   * @return 文件字节流   */  public ResponseEntity<byte[]> export(File file) {    return export(file.getName(), file);  }    /**   * 下载文件通用方法   *   * @param fileName 文件名称   * @param file   文件对象   * @return 文件字节流   */  public ResponseEntity<byte[]> export(String fileName, File file) {     HttpHeaders headers = new HttpHeaders();    headers.setContentType(MediaType.APPLICATION_OCTET_STREAM);     headers.setContentDispositionFormData("attachment", encodeFileName(fileName));    ResponseEntity<byte[]> rs = null;    try {      // 这里不能使用 HttpStatus.CREATED 201 是因为 IE Edge 无法识别，但是Firefox chrome 没问题      rs = new ResponseEntity<>(FileUtils.readFileToByteArray(file),          headers, HttpStatus.OK);    } catch (IOException e) {      //throw new CommonException(ResponseStatusEnum.FILE_ERROR, e);    }    return rs;  }   /**   * 下载文件的名称，这个是在浏览器那里显示的名称   *   * @param fileName 文件名称   * @return 加码的文件名称   * <p>   * IE   * Mozilla/5.0 (Windows NT 10.0; WOW64; Trident/7.0; rv:11.0) like Gecko   * <p>   * Edge   * Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/46.0.2486.0 Safari/537.36 Edge/13.10586   * <p>   * Firefox   * Mozilla/5.0 (Windows NT 10.0; WOW64; rv:46.0) Gecko/20100101 Firefox/46.0   * <p>   * Chrome   * Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/47.0.2526.106 Safari/537.36   */  private String encodeFileName(String fileName) {    String name = fileName;    try {      String agent = request.getHeader("USER-AGENT").toLowerCase();      if (null != agent && (agent.contains("msie") || agent.contains("edge"))) { // IE edge        name = URLEncoder.encode(fileName, "UTF-8");      } else if (agent.contains("safari") || agent.contains("chrome") || agent.contains("firefox")) { // safari chrome firefox        name = new String(fileName.getBytes("UTF-8"), "iso-8859-1");      } else { // IE10 IE11        name = URLEncoder.encode(fileName, "UTF-8");      }      // 把加号还原为空格(IE Edge 有问题)      name = name.replace("+", "%20");    } catch (UnsupportedEncodingException e) {      //throw new CommonException(ResponseStatusEnum.FAILURE, e);    }    return name;  }  }