Servlet supports uploading multiple images

The first front-end form is this form:

<form target= "_self" method= "post" action= "Fileuploadmultyservlet" enctype= "Multipart/form-data" >

<label> upload material <input type= "file" id= "image" Name= ' image ' ></label>
<label> upload material <input type= "file" id= "Image1" Name= ' Image1 ' ></label>
<label> upload material <input type= "file" id= "Image2" Name= ' Image2 ' ></label>
<input type= "Submit" class= "Btn-u" value= "Commit" >

</form>

Then upload the image with the servlet code as follows:

public class Fileuploadmultyservlet extends HttpServlet {

Private static final long serialversionuid = 1L;
Private File Uploadpath;
Private File TempPath;

@Override
public void Init () throws Servletexception {

Uploadpath = new File (Getservletcontext (). Getrealpath ("upload"));
System.out.println ("uploadpath=====" + Uploadpath);
If the directory does not exist
if (!uploadpath.exists ()) {
Create a Directory
Uploadpath.mkdir ();
}

Temp directory
File Tempfile = new file (Item.getname ()) constructs a temporary object
TempPath = new File (Getservletcontext (). Getrealpath ("temp"));
if (!temppath.exists ()) {
Temppath.mkdir ();
}

If you do not show the call to the parent class method, there will be no itemmanager instance, so it will cause a null pointer
Super.init ();

}

public void doget (HttpServletRequest request, httpservletresponse response)
Throws Servletexception, IOException {
DoPost (request, response);
}

@SuppressWarnings ("deprecation")
public void DoPost (HttpServletRequest request, httpservletresponse response)
Throws Servletexception, IOException {

Fetch data from item_upload.jsp, because the encoding format of the upload page is different from the general one, using enctype= "Multipart/form-data"
form submission using Multipart/form-data, unable to obtain data using Req.getparameter ()
String ItemNo = Req.getparameter ("ItemNo");
System.out.println ("itemno======" + ItemNo);

/******************************** using the FileUpload component to parse the form ********************/
Boolean ismultipart = servletfileupload.ismultipartcontent (request);
Diskfileitemfactory factory = new Diskfileitemfactory ();
Factory.setsizethreshold (4096);
Factory.setrepository (TempPath);
Servletfileupload upload = new Servletfileupload (factory);
Upload.setheaderencoding ("Utf-8");
Maximum size before a fileuploadexception'll be thrown
Upload.setsizemax (1000000 * 20);

Try {
list<?> items = upload.parserequest (request);
String data = "";
int i = 0;
String ItemNo = "";
String fileName = "";
Iterator iter = Items.iterator ();
while (Iter.hasnext ()) {
Fileitem item = (Fileitem) iter.next ();
if (Item.isformfield ()) {
String name = Item.getfieldname ();
i++;
data = item.getstring ();
if ("ItemNo". Equals (Item.getfieldname ())) {
ItemNo = item.getstring ();
}
}
//Is input= "type" input domain
Else if (!item.isformfield ()) {
//upload file name and full path
FileName = Item.getname ();
System.out.println ("filename===" +filename);
Long size = Item.getsize ();
//Determines whether the file is selected
if (fileName = = NULL | | filename.equals (")) && size = = 0) {
continue;
} else{
FileName = system.currenttimemillis () + ". jpg";
}
//intercept string such as: C:\WINDOWS\Debug\PASSWD. LOG
FileName = filename.substring (
filename.lastindexof ("\ \") + 1, filename.length ());

Save the file on the server's physical disk: The first parameter is: Full path (excluding file name) the second parameter is: file name
Item.write (file);
The modified file name and item name are consistent, and you have forcibly modified the filename extension gif
Item.write (New File (Uploadpath, ItemNo + ". gif"));
Save the file to the directory without modifying the filename
Item.write (New File (Uploadpath, fileName));
}
}
Response.sendredirect (Request.getcontextpath () + "/people_require.html");
} catch (Exception e) {
E.printstacktrace ();
}

}
}

Finally, you can see three images in the upload under your Tomcat project path, with the following effects:

Servlet supports uploading multiple images