public static void write(HttpServletResponse response, InputStream in, int bufferSize) {
		ServletOutputStream out = null;
		try {
			out = response.getOutputStream();
			IoUtil.copy(in, out, bufferSize);
		} catch (IOException e) {
			throw new UtilException(e);
		} finally {
			IoUtil.close(out);
			IoUtil.close(in);
		}
	}
public static void write ( HttpServletResponse response , InputStream in , int bufferSize ) { ServletOutputStream out = null ; try { out = response . getOutputStream ( ) ; IoUtil . copy ( in , out , bufferSize ) ; } catch ( IOException e ) { throw new UtilException ( e ) ; } finally { IoUtil . close ( out ) ; IoUtil . close ( in ) ; } }
返回数据给客户端

@param response 响应对象{@link HttpServletResponse}
@param in 需要返回客户端的内容
@param bufferSize 缓存大小