文件上传工具

梦里梦外; 2022-05-27 02:20 203阅读 0赞

package cn.itcast.util;  
  
  
import java.io.ByteArrayOutputStream;  
import java.io.File;  
import java.io.FileInputStream;  
import java.io.IOException;  
  
  
import javax.servlet.ServletOutputStream;  
import javax.servlet.http.HttpServletResponse;  
  
  
public class DownloadUtil \{  
  
/\*\*  
 \* @param filePath 要下载的文件路径  
 \* @param returnName 返回的文件名  
 \* @param response HttpServletResponse  
 \* @param delFlag 是否删除文件  
 \*/  
protected void download(String filePath,String returnName,HttpServletResponse response,boolean delFlag)\{  
this.prototypeDownload(new File(filePath), returnName, response, delFlag);  
\}  
  
  
  
  
/\*\*  
 \* @param file 要下载的文件  
 \* @param returnName 返回的文件名  
 \* @param response HttpServletResponse  
 \* @param delFlag 是否删除文件  
 \*/  
protected void download(File file,String returnName,HttpServletResponse response,boolean delFlag)\{  
this.prototypeDownload(file, returnName, response, delFlag);  
\}  
  
/\*\*  
 \* @param file 要下载的文件  
 \* @param returnName 返回的文件名  
 \* @param response HttpServletResponse  
 \* @param delFlag 是否删除文件  
 \*/  
public void prototypeDownload(File file,String returnName,HttpServletResponse response,boolean delFlag)\{  
// 下载文件  
FileInputStream inputStream = null;  
ServletOutputStream outputStream = null;  
try \{  
if(!file.exists()) return;  
response.reset();  
//设置响应类型 PDF文件为"application/pdf"，WORD文件为："application/msword"， EXCEL文件为："application/vnd.ms-excel"。    
response.setContentType("application/octet-stream;charset=utf-8");  
  
  
//设置响应的文件名称,并转换成中文编码  
//returnName = URLEncoder.encode(returnName,"UTF-8");  
returnName = response.encodeURL(new String(returnName.getBytes(),"iso8859-1")); //保存的文件名,必须和页面编码一致,否则乱码  
  
//attachment作为附件下载；inline客户端机器有安装匹配程序，则直接打开；注意改变配置，清除缓存，否则可能不能看到效果  
response.addHeader("Content-Disposition",   "attachment;filename="+returnName);    
  
//将文件读入响应流  
inputStream = new FileInputStream(file);  
outputStream = response.getOutputStream();  
int length = 1024;  
int readLength=0;  
byte buf\[\] = new byte\[1024\];  
readLength = inputStream.read(buf, 0, length);  
while (readLength != -1) \{  
outputStream.write(buf, 0, readLength);  
readLength = inputStream.read(buf, 0, length);  
\}  
\} catch (Exception e) \{  
e.printStackTrace();  
\} finally \{  
try \{  
outputStream.flush();  
\} catch (IOException e) \{  
e.printStackTrace();  
\}  
try \{  
outputStream.close();  
\} catch (IOException e) \{  
e.printStackTrace();  
\}  
try \{  
inputStream.close();  
\} catch (IOException e) \{  
e.printStackTrace();  
\}  
//删除原文件  
  
if(delFlag) \{   
file.delete();  
\}  
\}  
\}  
  
  
/\*\*  
 \* by tony 2013-10-17  
 \* @param byteArrayOutputStream 将文件内容写入ByteArrayOutputStream  
 \* @param response HttpServletResponse 写入response  
 \* @param returnName 返回的文件名  
 \*/  
public void download(ByteArrayOutputStream byteArrayOutputStream, HttpServletResponse response, String returnName) throws IOException\{  
response.setContentType("application/octet-stream;charset=utf-8");  
returnName = response.encodeURL(new String(returnName.getBytes(),"iso8859-1")); //保存的文件名,必须和页面编码一致,否则乱码  
response.addHeader("Content-Disposition",   "attachment;filename=" + returnName);    
response.setContentLength(byteArrayOutputStream.size());  
  
ServletOutputStream outputstream = response.getOutputStream(); //取得输出流  
byteArrayOutputStream.writeTo(outputstream); //写到输出流  
byteArrayOutputStream.close(); //关闭  
outputstream.flush(); //刷数据  
\}

案例  (WorkBook workBook=new HSSFWorkBook())

![70][]

[70]: /images/20220527/2c9a4b94e2a746f3b083539f21debc57.png