fix bug:文件夹目录重复.

examcloud-core-questions-service/src/main/java/cn/com/qmth/examcloud/core/questions/service/impl/ExtractConfigFileServiceImpl.java

@@ -189,8 +189,9 @@ public class ExtractConfigFileServiceImpl implements ExtractConfigFileService {
 
 	@Override
 	public void exportExamPaperInfo(ExportPaperInfoModel exportModel,HttpServletResponse response,String loginName) throws Exception {
-		String downloadDir = downloadDirectory + loginName;
-		String downZipDir = zipDirectory + loginName; 
+		String tempDir = loginName + System.currentTimeMillis();
+		String downloadDir = downloadDirectory +"/"+ tempDir;
+		String downZipDir = zipDirectory +"/"+ tempDir;
 		//创建试卷和压缩文件 文件夹
 		FileDisposeUtil.createDirectory(downloadDir);
 		//创建压缩文件的文件夹