flex与java集成下载功能实现

?适用于附件放在数据库中的下载方式

?flex端：

 
 

navigateToURL(new?URLRequest("URL.do"+id),?"_blank"); --发送的请求路径
 
 

java端:

?

 
 

package?com.zjht.hrm.action;?
  
  
?
  
  
import?java.io.BufferedOutputStream;?
  
  
import?java.io.IOException;?
  
  
import?java.io.OutputStream;?
  
  
import?java.io.PrintWriter;?
  
  
import?org.apache.commons.codec.binary.*;?
  
  
import?javax.servlet.http.HttpServletRequest;?
  
  
import?javax.servlet.http.HttpServletResponse;?
  
  
?
  
  
import?nl.bitwalker.useragentutils.Browser;?
  
  
import?nl.bitwalker.useragentutils.UserAgent;?
  
  
?
  
  
import?org.springframework.stereotype.Controller;?
  
  
import?org.springframework.web.bind.annotation.RequestMapping;?
  
  
import?org.springframework.web.bind.annotation.RequestMethod;?
  
  
?
  
  
import?com.zjht.hrm.dao.AttachmentDao;?
  
  
import?com.zjht.hrm.model.Attachment;?
  
  
?
  
  
@Controller?
  
  
public?class?AttachmentDownloadAction?{?
  
  
?
  
  
????private?AttachmentDao?attachmentDao;?
  
  
?
  
  
????@RequestMapping(value?=?"AttachmentDownload",?method?=?RequestMethod.GET)?
  
  
????public?void?attachmentDownloadById(final?long?id,?final?boolean?fail,?
  
  
????????????final?HttpServletRequest?request,?final?HttpServletResponse?response)?{?
  
  
????????Attachment?entity?=?null;?
  
  
????????try?{?
  
  
????????????entity?=?attachmentDao.findById(id);?
  
  
????????????if(entity==null){?
  
  
????????????????try?{?
  
  
????????????????????response.sendError(HttpServletResponse.SC_FORBIDDEN);?
  
  
????????????????????return;?
  
  
????????????????}?catch?(IOException?e)?{?
  
  
????????????????}?
  
  
????????????}?
  
  
????????????byte[]?data?=?entity.getContent();?
  
  
????????????String?fileName?=?entity.getFileName()?==?null???""?:?entity?
  
  
????????????????????.getFileName();?
  
  
????????????if?(isImage(entity.getFileType())?&&?!fail)?{?
  
  
????????????????//imageDownload(request,?response,?entity);?
  
  
????????????????PrintWriter?out?=?response.getWriter();?
  
  
????????????????out.println("<img?src="AttachmentDownload.do?id="+entity.getId()?
  
  
????????????????????????+"&fail=true"?/>");?
  
  
????????????????out.flush();?
  
  
????????????????out.close();?
  
  
????????????????return;?
  
  
????????????}?
  
  
????????????response.reset();?
  
  
????????????response.setStatus(200);?
  
  
????????????FileType?fileType=getFileType(entity.getFileType());?
  
  
????????????UserAgent?userAgent?=?UserAgent.parseUserAgentString(request?
  
  
????????????????????.getHeader("user-agent"));?
  
  
????????????if?(userAgent.getBrowser().getGroup()?==?Browser.IE)?
  
  
????????????????fileName=java.net.URLEncoder.encode(fileName,"UTF-8");?
  
  
????????????else?
  
  
????????????????fileName?=?new?String(fileName.getBytes("UTF-8"),"ISO8859_1");?
  
  
????????????if(fileType==FileType.img?||?fileType==FileType.pdf)?
  
  
????????????{?
  
  
????????????????response.setHeader("Content-Disposition",?"inline;?filename=""?
  
  
????????????????????????+?fileName?+?""");?
  
  
????????????}else{?
  
  
????????????????response.setHeader("Content-Disposition",?"attachment;?filename=""?
  
  
????????????????????????+?fileName?+?""");?
  
  
????????????}?
  
  
????????????response.addHeader("Content-Length",?""?+?data.length);?
  
  
????????????response.setHeader("Connection",?"close");?
  
  
????????????response.setContentType(getContentType(entity.getFileType()));?
  
  
????????????OutputStream?outputStream?=?new?BufferedOutputStream(?
  
  
????????????????????response.getOutputStream());?
  
  
????????????outputStream.write(data);?
  
  
????????????outputStream.flush();?
  
  
????????????outputStream.close();?
  
  
????????}?catch?(Exception?e1)?{?
  
  
????????????try?{?
  
  
????????????????response.sendError(HttpServletResponse.SC_FORBIDDEN);?
  
  
????????????}?catch?(IOException?e)?{?
  
  
????????????}?
  
  
????????}?
  
  
?
  
  
????}?
  
  
?
  
  
????@SuppressWarnings("unused")?
  
  
????private?void?imageDownload(final?HttpServletRequest?request,?
  
  
????????????final?HttpServletResponse?response,?Attachment?entity)?
  
  
????????????throws?IOException?{?
  
  
????????PrintWriter?out?=?response.getWriter();?
  
  
????????UserAgent?userAgent?=?UserAgent.parseUserAgentString(request?
  
  
????????????????.getHeader("user-agent"));?
  
  
????????if?(userAgent.getBrowser()?==?Browser.IE5?
  
  
????????????????||?userAgent.getBrowser()?==?Browser.IE5_5?
  
  
????????????????||?userAgent.getBrowser()?==?Browser.IE6?
  
  
????????????????||?userAgent.getBrowser()?==?Browser.IE7)?{?
  
  
????????????out.println("<img?src="AttachmentDownload.do?id="+entity.getId()?
  
  
????????????????????+"&fail=true"?/>");?
  
  
?
  
  
????????}?else?{?
  
  
????????????String?content?=?Base64.encodeBase64String(entity.getContent());?
  
  
????????????out.println("<img?src="data:image/"?+?entity.getFileType()?
  
  
????????????????????+?";base64,"?+?content?+?""?/>");?
  
  
????????}?
  
  
????????out.flush();?
  
  
????????out.close();?
  
  
????}?
  
  
?
  
  
????public?void?setAttachmentDao(AttachmentDao?attachmentDao)?{?
  
  
????????this.attachmentDao?=?attachmentDao;?
  
  
????}?
  
  
?
  
  
????private?String?getContentType(String?extension)?{?
  
  
????????FileType?fileType?=?null;?
  
  
????????try?{?
  
  
????????????fileType?=?Enum.valueOf(FileType.class,?extension);?
  
  
????????}?catch?(Exception?e)?{?
  
  
????????????return?"application/octet-stream;charset=UTF-8";?
  
  
????????}?
  
  
????????switch?(fileType)?{?
  
  
????????case?xls:?
  
  
????????????//?contentType设定?
  
  
????????????return?"application/vnd.ms-excel;charset=utf-8";?
  
  
????????case?xlsx:?
  
  
????????????//?contentType设定?
  
  
????????????return?"application/vnd.ms-excel;charset=utf-8";?
  
  
????????case?pdf:?
  
  
????????????//?contentType设定?
  
  
????????????return?"application/pdf;charset=utf-8";?
  
  
????????case?doc:?
  
  
????????????//?contentType设定?
  
  
????????????return?"application/msword;charset=utf-8";?
  
  
????????case?docx:?
  
  
????????????//?contentType设定?
  
  
????????????return?"application/msword;charset=utf-8";?
  
  
????????case?txt:?
  
  
????????????//?contentType设定?
  
  
????????????return?"text/plain;charset=utf-8";?
  
  
????????default:?
  
  
????????????//?contentType设定?
  
  
????????????return?"application/octet-stream;charset=UTF-8";?
  
  
????????}?
  
  
????}?
  
  
?
  
  
????public?enum?FileType?{?
  
  
????????xls("xls"),?xlsx("xlsx"),?pdf("pdf"),?doc("doc"),?docx("docx"),?txt(?
  
  
????????????????"txt"),gif("gif"),jpeg("jpeg"),jpg("jpg"),png("png"),img("img");?
  
  
?
  
  
????????FileType(String?name)?{?
  
  
????????????this.name?=?name;?
  
  
????????}?
  
  
?
  
  
????????private?String?name;?
  
  
?
  
  
????????public?String?getName()?{?
  
  
????????????return?name;?
  
  
????????}?
  
  
?
  
  
????????public?void?setName(String?name)?{?
  
  
????????????this.name?=?name;?
  
  
????????}?
  
  
????}?
  
  
?????
  
  
????private?FileType?getFileType(String?extension){?
  
  
????????FileType?fileType?=?null;?
  
  
????????try?{?
  
  
????????????fileType?=?Enum.valueOf(FileType.class,?extension);?
  
  
????????}?catch?(Exception?e)?{?
  
  
????????????return?null;?
  
  
????????}?
  
  
????????switch?(fileType)?{?
  
  
????????case?pdf:?
  
  
????????????return?fileType;?
  
  
????????case?gif:?
  
  
????????????return?FileType.img;?
  
  
????????case?jpeg:?
  
  
????????????return?FileType.img;?
  
  
????????case?jpg:?
  
  
????????????return?FileType.img;?
  
  
????????case?png:?
  
  
????????????return?FileType.img;?
  
  
????????default:?
  
  
????????????return?null;?
  
  
????????}?
  
  
????}?
  
  
?????
  
  
?
  
  
????private?boolean?isImage(String?fileType)?{?
  
  
????????if?(fileType.equals("png")?||?fileType.equals("gif")?
  
  
????????????????||?fileType.equals("jpg"))?{?
  
  
????????????return?true;?
  
  
????????}?else?{?
  
  
????????????return?false;?
  
  
????????}?
  
  
????}?
  
  
}?