下载文件

public class DownLoad {
/**
 * @author lidongbo
 */
    private  Logger logger = Logger.getLogger(DownExcel.class);
    public void downLoad(String filePath, HttpServletResponse response)  {
        File f = new File(filePath);
        if (!f.exists()) {
            return;
        }
        BufferedInputStream in;
        try {
            in = new BufferedInputStream(new FileInputStream(f));
            byte[] buf = new byte[1024];
            int len = 0;
            response.reset(); 
            response.setContentType("application/x-msdownload");
            response.setHeader("Content-Disposition", "attachment; filename="+ f.getName());
            OutputStream out=null;
            try {
                out = response.getOutputStream();
                out.flush();
                while ((len = in.read(buf)) > 0 & in != null){
                    out.write(buf, 0, len);
                }
                in.close();
                out.close();
            }catch (IOException e) {
                e.printStackTrace();
                logger.error(e.getMessage(), e);
            }finally{
                try {
                    in.close();
                    out.close();
                } catch (IOException e) {
                    e.printStackTrace();
                    logger.error(e.getMessage(), e);
                }
            } 
        } catch (FileNotFoundException e) {
            e.printStackTrace();
            logger.error(e.getMessage(), e);
        } 
    }
    
 
  
}