Changes that need to be read request to the servlet request with no response after the excel file, f-CodePudding

Front two excel spreadsheet is directly read, front-end validation normally submit the servlet read write database, followed by a after the discovery of the error is read in excel form validation, open the excel spreadsheet correct mistakes, to read the data uploading front launched a request the request, the back-end servlet no response, is for what is going wrong? If I refresh the page again, be equivalent to each functional module closed set back to the home page and upload to read the file, and then, don't know where the problem is, is part of the front-end back-end code below, please help correct, thank you

 
Js part 
//bulk import student information 
$(" # import "). Click (function () {
$. Messenger. Confirm (" remind ", "information will be batch import students! Confirm to continue ", function (r) {
If (r) {
$(" # batchImportDialog "). The dialog (" open "); 
} 
}); 
}); 
//batch add student information dialog 
$(" # batchImportDialog "). The dialog ({
Title: "bulk import student information," 
Width: 650, 
Height: 460, 
IconCls: "icon - edit," 
Modal: true, 
Collapsible: false, 
Minimizable: false, 
Maximizable: false, 
Draggable: true, 
Closed: true, 
Buttons: [
{
Text: 'upload file', 
Plain: true, 
IconCls: 'icon - user_add', 
Handler: function () {
/* var validate=$(" # addForm "). The form (" validate "); 
if(! Validate) {
$. Messenger. Alert (" remind ", please check your input data! "" , "warning"); 
return; 
} else {
Var gradeid=$(" # add_gradeList "). The combobox (" getValue "); 
Var clazzid=$(" # add_clazzList "). The combobox (" getValue "); */
Var form=new FormData (document. GetElementById (" batchImportForm ")); 
$. Ajax ({
Type: "post", 
Url: "StudentServlet? Method=BatchImportStudent& T="+ new Date (). GetTime (), 
Data: the form, 
ProcessData: false, 
ContentType: false, 
Success: the function (MSG) {
{if (MSG=="success") 
$. Messenger. Alert (" remind ", "information batch import students success", "info"); 
//to refresh the form 
$(" # dataList "). The datagrid (" reload "); 
$(" # dataList "). The datagrid (" uncheckAll "); 
} else {
$. Messenger. Alert (" remind ", MSG, "warning"); 
return; 
} 
} 
}); 
} 
}, 
] 
}); 

$(' # fb) filebox ({
ButtonText: 'select files, 
ButtonAlign: 'right', 
Accept: application/VND. - ms excel, 
}); 
HTML part

 
The back-end code section 
//read excel spreadsheet information, bulk import database 
Private void batchImportStudent (it request, HttpServletResponse response) {
response.setContentType("text/html; Charset=utf-8 "); 
System. The out. Println (" batch upload button "); 
Try {
//import database header template 
String [] databaseTitleTemp={" number ", "name", "sex", "phone", "qq", "clazzid", "gradeid"}; 
String [] titleNameList=new String [databaseTitleTemp length]. 
Object [] gradeclazzid=null; 
//create factory 
DiskFileItemFactory factory=new DiskFileItemFactory (); 
String path=this. GetServletContext (.) getRealPath ("/upload "); 
The File f=new File (path); 
if(! F.e xists ()) {
f.mkdirs(); 
} 
//Settings file cache path 
Factory. SetRepository (f); 
//create the fileupload component 
ServletFileUpload fileupload=new ServletFileUpload (factory); 
Fileupload. SetHeaderEncoding (" GBK "); 
//parse request 
List Fileitems=fileupload. ParseRequest (request); 
PrintWriter writer.=the response getWriter (); 
//traverse collection 
First: the for (FileItem FileItem: fileitems) {
//determine whether for ordinary field 
If (fileitem isFormField ()) {
//get the field name and field value 
String name=fileitem. GetFieldName (); 
String value=https://bbs.csdn.net/topics/fileitem.getString (" GBK "); 
} else {
//upload file path 
The String filename=fileitem. GetName (); 
//subtracted filename 
Filename=filename. The substring (filename. LastIndexOf (" \ \ ") + 1); 
//file name needs to be the only 
Filename=UUID. RandomUUID (). The toString () + "_" + filename; 
//a file on the server to create 
String webPath="/upload/"; 
String filepath=getServletContext (.) getRealPath (webPath + filename); 
//create a file 
The File File=new File (filepath); 
file.getParentFile().mkdirs(); 
file.createNewFile(); 
//get uploaded file stream 
InputStream in=fileitem. GetInputStream (); 
HSSFSheet sheet=bimportStudent. GetSheet (in); 
//get form total number of rows 
Int rows=bimportStudent. GetTotalRows (sheet); 
//obtained form the total number of columns 
Int columns=bimportStudent. GetTotalColumns (sheet); 
First line//upload form template 
String [] titleNameTemp={" student id ", "name", "gender", "phone", "QQ", "class", "grade"}; 
ExcelDataValidate ExcelDataValidate=new ExcelDataValidate (); 
//contrast and upload form template first line are consistent 
String validateTitleInfo=excelDataValidate. TitleNameCompare (titleNameTemp bimportStudent, sheet); 
if(! ValidateTitleInfo. Equals (" true ")) {
Writer. Print (validateTitleInfo); 
ValidateTitleInfo=null; 
in.close(); 
Break first. 
} else {
for(int i=0; ITitleNameList [I]=databaseTitleTemp [I]; 
} 
} 
//data validity check upload form 
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