We Keep Coding

Upload files in folder/subdirectories using webkitDirectory and Java Servlet

I am trying to implement a file-upload functionality using webkitdirectory with java backend.
Step1. Design a HTML form with webkitdirectory
<form action="DataUpload" method="post" enctype="multipart/form-data">
<input type="text" name="dbName" value="Database Name Here" id="dbName"/>
<input type="file" id="ctrl" webkitdirectory directory multiple/>
<input type="submit" />
</form>
Step 2. Passing information from form to Servlet
public class DataUpload extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response){
ServletFileUpload upload = new ServletFileUpload();
FileItemIterator fileIterator;
try {
fileIterator = upload.getItemIterator(request);
InputStream inputStream = null;
BufferedReader br = null;
System.out.println("CheckPoint 1");
while(fileIterator.hasNext()) {
System.out.println("CheckPoint 2");
FileItemStream item = fileIterator.next();
String inputFileName = FilenameUtils.getName(item.getName());
inputStream = item.openStream();
inputFileName = inputFileName.split("\\.")[0];
List<String[]> list = new ArrayList<String[]>();
// Getting File
br = new BufferedReader(new InputStreamReader(inputStream)); // Getting the object to read file
String line;
while((line = br.readLine())!= null){// While condition ends then end of file is reached.
list.add(line.split(","));
}
// Checking if File is Empty
if (list.size() == 0){
System.err.println("File Empty");
}else{
// TODO : Parameter Parser.
// DO JOB HERE
}
}
} catch (FileUploadException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
My code, doesn't give any programming error, but it does not pass through the CheckPoint 2, i.e. it doesn't go inside the while loop. I tried looking into various post, such as:
Keep Directory Structure When Uploading
How to upload files to server using JSP/Servlet? - While this question shows maximum resemblance to problem in question, This question works for selecting multiple files in a folder, where the problem here is question is to upload files in different sub directories inside a folder.
I was wondering, if this was possible using solely java servlets without using javascript. I was able to upload multiple files inside a single folder. But, code doesn't seem to work, when I select a folder as input, instead it works when I select a particular file or a subset of files.

HTML File Form
<form onsubmit="readFiles()">
<input type="file" name="files" webkitdirectory directory multiple id="files">
<input type="submit">
</form>
JavaScript Function
function readFiles(){
var files = document.getElementById("files").files;
for (var file = 0 ; file < files.length; file++) {
var reader = new FileReader();
reader.onload = function(e){
var object = new Object();
object.content = e.target.content;
var json_upload = "jsonObject=" + JSON.stringify(object);
var xmlhttp = new XMLHttpRequest(); // new HttpRequest instance
xmlhttp.open("POST", "http://localhost:8080/readFileServlet");
xmlhttp.setRequestHeader("Content-Type", "application/x-www-form-urlencoded");
xmlhttp.send(json_upload);
}
reader.readAsBinaryString(files);
}
}
Java Function:
JSONObject jObj = new JSONObject(request.getParameter("jsonObject"));

in a post method try
make #Autowired ServletContext c;
or take object from it in servlets
byte[] bytes = file.getBytes();
String UPLOAD_FOLDEdR=c.getRealPath("/images");
Path path = Paths.get(UPLOAD_FOLDEdR +"/"+ file.getOriginalFilename());
Files.write(path, bytes);

Using multipart/form-data Form [duplicate]

This question already has answers here:
How can I upload files to a server using JSP/Servlet?
(14 answers)
Closed 7 years ago.
I am writing an Application to Upload Image files in to the server.
I am declaring a form giving the type as enctype="multipart/form-data">
I have declare few hidden variables also inside this form. When I am trying to get the Values of these hidden variable inside a Servlet it comes as "Null".
If I remove the enctype, I could retrieve the correct values of the variable.
JSP Form :
<FORM name="form1" enctype="multipart/form-data"><!-- T1787NM -->
<input type=hidden name="stringurl" value="<%=stringurl%>">
<input type=hidden name="savetype" value="<%=ACTION%>">
<INPUT type="hidden" name="iReq" value="<%=iReq%>">
<INPUT type="File" name="FileUpload" id="fileInput">
</FORM>
Servlet :
String stringurl=(String) req.getParameter("stringurl");
other code..
I want to know how to access these variables in Servlet. Thanks in Advance.

You need to write following code in servlet
boolean isMultipart = ServletFileUpload.isMultipartContent(request);
if (!isMultipart) {
} else {
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
List<?> items = null;
String stringUrl = null;
try {
items = upload.parseRequest(request);
} catch (FileUploadException e) {
e.printStackTrace();
}
Iterator<?> itr = items.iterator();
while (itr.hasNext()) {
FileItem item = (FileItem) itr.next();
if (item.isFormField()) {
System.out.println("Form Field");
String parameterName = item.getName();
if(parameterName.equals("stringurl")) {
stringUrl = item.getString();
}
} else {
// upload file logic here
}
}
}
likewise you need to get all other form fields using if else ladder.
Also you have to add commons-fileupload.jar, commons-logging.jar and commons-io.jar to project build path.

Identifying input tag in servlet

In my file upload servlet, I have 4 input tags as follows
<li>Left File : <input type="file" name="dataFile1" id="fileChooser1" /></li><li><br></li>
<li>Right File : <input type="file" name="dataFile2" id="fileChooser2" /></li><li><br></li>
<li>Config File :<input type="file" name="dataFile3" id="fileChooser3" /></li><li><br></li>
<li>final File : <input type="file" name="dataFile4" id="fileChooser4" /></li><li><br></li>
<li><button type="button" id="execute" onclick="ValidateFile()">Click to Upload files</button></li>
Now, in my upload.java I want to identify which file from which input is being uploaded.
I've tried using,
String file1 = request.getParameter("dataFile1").toString();
String file2 = request.getParameter("dataFile2").toString();
String file3 = request.getParameter("dataFile3").toString();
String file4 = request.getParameter("dataFile4").toString();
and
if (file1 != null)
{
//use apache commons and upload file
out.println("left file uploaded");
}
But this does not work.
How to identify from which input tag the file is being uploaded?

this is not the way you deal with file uploads
Maybe check this answer
The relevant part is that ServletFileUpload and FileItem from apache commons-fileupload is used, in turn FileItem has a method to get the field name.
Here is some sample code (from the answer linked above):
FileItemFactory factory = new DiskFileItemFactory();
ServletFileUpload upload = new ServletFileUpload(factory);
List items = null;
try {
items = upload.parseRequest(request);
} catch (FileUploadException e) {
e.printStackTrace();
}
Iterator itr = items.iterator();
while (itr.hasNext()) {
FileItem item = (FileItem) itr.next();
if (item.isFormField()) {
} else {
try {
String itemName = item.getName();
String itemField = item.getFieldName();
if (itemField.equals("datafile1")) {
// do things for left side
} else if (itemField.equals("datafile2")) {
// do things for right side
}
} catch (Exception e) {
e.printStackTrace();
}
}
}

Commons FileUpload. Empty Items list

I use apache commons file-upload to upload files on servlet. But after parsing request I always get empty list of file items. My code looks like this:
if (!ServletFileUpload.isMultipartContent(request)) {
throw new UnsupportedOperationException("Expected `multipart/...` content-type header ");
}
ServletFileUpload upload = new ServletFileUpload(new DiskFileItemFactory());
List<FileItem> items = upload.parseRequest(request);
logger.debug("Items size: " + items.size());
Where can be problem? Request sent correctly

Add enctype="multipart/form-data" in your form action
<form action="UploadServlet" method="post"
enctype="multipart/form-data">
</form>
DiskFileItemFactory factory = new DiskFileItemFactory();
// maximum size that will be stored in memory
factory.setSizeThreshold(maxMemSize);
// Location to save data that is larger than maxMemSize.
factory.setRepository(new File("c:\\temp"));
// Create a new file upload handler
ServletFileUpload upload = new ServletFileUpload(factory);
// maximum file size to be uploaded.
upload.setSizeMax( maxFileSize );
try{
// Parse the request to get file items.
List fileItems = upload.parseRequest(request);
}catch(Exception e){
}
http://www.tutorialspoint.com/servlets/servlets-file-uploading.htm

When creating the DiskFileItemDirectory use this this constructor
DiskFileItemFactory factory = new DiskFileItemFactory(FILE_SIZE, new File("/yourfolder"));
The FILE_SIZE is max file size you allow to upload. Make sure you have permissions to the folder location at "/yourfolder" (change this ...)

File Uploading with Servlets? [duplicate]

This question already has answers here:
How can I upload files to a server using JSP/Servlet?
(14 answers)
Closed 3 years ago.
Note:
Before reading this question and its answer, please check your input element has name attribute.
I am trying to upload file using servlet. Eclipse console shows no errors. But the file is not getting uploaded. For me, it seems everything is fine. But I am making mistake somewhere.
In console I get just
Inside Servlet //Printed by code
Items: [] // Printed by Cdoe
Html Code:
<form action="ImageUploadServlet" method="post" enctype="multipart/form-data">
<table>
<tr>
<td><label>Select Image: </label></td>
<td><input type="file" id="sourceImage" /></td>
<tr>
<td colspan="3">
<input type="submit" value="Upload"/><span id="result"></span>
</td>
</tr>
</table>
</form>
Servlet Code:
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
boolean isMultiPart = ServletFileUpload.isMultipartContent(request);
System.out.println("Inside Servlet");
if(!isMultiPart){
System.out.println("Form type is not multipart/form-data");
System.out.println("File Not Uploaded");
}
else
{
FileItemFactory dfit = new DiskFileItemFactory();
ServletFileUpload sfu = new ServletFileUpload(dfit);
List aList = null;
try {
aList = sfu.parseRequest(request);
System.out.println("Items: "+aList);
}
catch (FileUploadException fue)
{
fue.printStackTrace();
}
Iterator itr = aList.iterator();
while(itr.hasNext())
{
FileItem fi = (FileItem) itr.next();
if(fi.isFormField())
{
System.out.println("File Name: "+fi.getFieldName());
System.out.println("File Size: "+fi.getSize());
try
{
File f = new File("D:/MyUploads/", fi.getName());
fi.write(f);
}
catch (Exception e)
{
e.printStackTrace();
}
}
else
{
System.out.println("It's Not Form Item;");
}
}
}
}
}
Any suggestions would be appreciated.
Thanks!

There are two problems:
First, you need to give the field a name. It becomes then the request parameter name.
<input type="file" id="sourceImage" name="sourceImage" />
Second, you need to handle the file uploads in the else case of FileItem#isFormField() as per the commons fileupload guide. Your code is currently ignoring them and doing only a sysout.
if (item.isFormField()) {
// Process regular form field (input type="text|radio|checkbox|etc", select, etc).
String fieldname = item.getFieldName();
String fieldvalue = item.getString();
// ... (do your regular form field processing job here)
} else {
// Process form file field (input type="file").
String fieldname = item.getFieldName();
String filename = FilenameUtils.getName(item.getName());
// ... (do your uploaded file job here)
File file = new File("D:/MyUploads/", filename);
item.write(file);
}
Note that you need to use FilenameUtils#getName() to extract the file name, because MSIE browser incorrectly sends the full client side file path along the file name. See also Commons FileUpload FAQ.
You also need to keep in mind that this approach will overwrite any previously uploaded file with the same name. You may want to add an autogenerated suffix to the filename.
See also:
How to upload files in JSP/Servlet?

Maybe this will help:
http://www.theserverside.com/news/1365153/HttpClient-and-FileUpload