Using the servlet to upload file functions

1.servlet just add a comment and use Request.getpart to get the value of the file, which is the servlet3.0 API

2. The form needs to add an attribute enctype= "Multipart/form-data"

Now attach the code

Form:

 <formMethod= "POST"Action= "Upload"enctype= "Multipart/form-data" >File:<inputtype= "File"name= "File"ID= "File" /> <BR/>Destination:<inputtype= "text"value= "F:"name= "Destination"/>            <BR/>            <inputtype= "Submit"value= "Upload"name= "Upload"ID= "Upload" />
</form>

Servlet:

Add these two notes to the class's reputation

@WebServlet (name = "Fileuploadservlet", Urlpatterns = {"/upload"})
@MultipartConfig

Custom methods:

The ProcessRequest method is to get the value of the file

protected voidProcessRequest (httpservletrequest request, httpservletresponse response)throwsservletexception, IOException {response.setcontenttype ("Text/html;charset=utf-8");
Request.setcharacterencoding ("Utf-8");
 　　　　　　 
Get pathFinalString Path = request.getparameter ("Destination");
Get the value of a fileFinalPart Filepart = Request.getpart ("File");        System.out.println (Filepart); FinalString FileName =GetFileName (Filepart); Manipulating files using IO stream outputstream out=NULL; InputStream filecontent=NULL; FinalPrintWriter writer =Response.getwriter (); Try{ out=NewFileOutputStream (NewFile (path +File.separator+fileName)); Filecontent=Filepart.getinputstream (); intRead; Final byte[] bytes =New byte[1024];  while(read = Filecontent.read (bytes))! =-1) {out.write (bytes,0, read); } writer.println ("New file" + FileName + "created at" +path); LOGGER.log (Level.info,"File {0} being uploaded to {1}",                    Newobject[]{filename, path}); } Catch(FileNotFoundException fne) {writer.println ("You either didn't specify a file to upload or is" + "trying to upload a file to a protected or none Xistent "+" location. "); Writer.println ("<br/> ERROR:" +fne.getmessage ()); LOGGER.log (Level.severe,"Problems during file upload. Error: {0} ",                    Newobject[]{fne.getmessage ()}); } finally {            if(Out! =NULL) {out.close (); }            if(Filecontent! =NULL) {filecontent.close (); }            if(Writer! =NULL) {writer.close (); }        }    }

The

GetFileName method is to get the file name

 private  String getfilename (final  Span style= "color: #000000;" > part) { final  String partheader = Part.getheader (" Content-disposition "); LOGGER.log (Level.info,  part Header = {0} ", Partheader);  for  (String content:part.getHeader ("Content-disposition"). Split (";"    Content.substring (Content.indexof ( ' = ') + 1). Trim (). replace ("\" "," " return  null  ;}  

And finally wrote it in the Dopost method.

protected void DoPost (httpservletrequest request, httpservletresponse response) throws servletexception, IOException {processrequest (request, response);}

It's all done here, the effect of the long passing success,

Using the servlet to upload file functions