java - How to customize the request from HTML to Servlet -

i building server using java's servlet , html forms.

i managed upload files: user reach html page, chose file he/she wants upload in his/her tree folder. file sent servlet i've written , downloaded on server (actually i'm running on localhost moment, server 'my documents' folder).

the next step make one: user (once logged, manage that) reaches html page, select file hosted server , download it.

to make it, have send 'download servlet' name of file. here questions:

• how list files in 'my documents' on html page.
• how send name of selected file servlet.
• how catch 'request' , make string of name out of it.

to precise these 2 lasts points, please have @ this:

list<fileitem> items = null; items = upload.parserequest(request); fileitem item = items.get(0); string filename = item.getname(); 

the block above catches name of folder in request. want do same thing if in request string (=catch string contained in request).

the file api give need selecting files in directory.

list<file> files = arrays.aslist(new file("/your/directory").listfiles());  list<string> filenames = new linkedlist<>(); (file file : files) {     filenames.add(someprefix + file.getname()); }  request.setattribute("filenames", filenames); 

i above because might not want give real path files, security reasons. once have list of file names in request attributes, can iterate on them in jsp.

<form ...>     select file:<br />     <c:foreach items="${filenames}" var="filename">         <input type="radio" name="filename" value="${filename}">     </c:foreach>     <input type="submit" name="submit" value="submit">submit </form> 

now files each attached input element, translate request parameter. when form submitted, can access select file name doing

string filename = request.getparameter("filename"); 

you can append file name directory structure , go , find on file system.