File class object doesn't delete files when running in a server java

Question

I've been working on my final programming class project, and I am stuck right now, I have to create an inventary for a company. I use textpad to write the code and the icarnegie workbench, to put the classes on it and run it, so the thing is that i have this servlet and from there I call the class called Delete, this class has various methods, each of them deletes a file, something like this:

import java.io.*;
public class Delete{

String nombre;


public Delete(String n){
 nombre=n;
 }


public void deleteNombre(){

File objt = new File("C:/Inventario/"+nombre+"/nombre.txt");
objt.delete();

 }

public void deleteCodigo(){

File objt = new File("C:/Inventario/"+nombre+"/codigo.txt");
objt.delete();

 }

public void deletePrecio(){

File objt = new File("C:/Inventario/"+nombre+"/precio.txt");
objt.delete();

 }

public void deleteCantidad(){

File objt = new File("C:/Inventario/"+nombre+"/cantidad.txt");
objt.delete();

 }



 }

When I try to call this from the servlet, I can compile successfully, I don't get any errors. when I put this code on a main class and run it, in terminal, the files are deleted, but when I use this method, calling it from a servlet, it just doesn't happen. How can this happen and how can I fix it?

Answer 1

Assuming that you've traced the code and these methods are actually getting called, this is possibly a permissions issue. Does the servlet container user have permission to access and alter those files?

That said, you probably wouldn't design a servlet application to mess around with the filesystem for non-binary data; typically you'd put this information in a database. It will avoid these permission issues, give you greater flexibility, and you wouldn't get into concurrent access issues (e.g. what happens if two users of your servlet try to access the file at the same time?)

Answer 2

The files are most likely still open somewhere else in the code.

Answer 3

A good starting point would be to check whether the file exists before deleting it and check for the return value of that delete() call. Something like:

File f = new File(something);
if(f.exists()) {
  if(!f.delete()) {
    System.out.println("Deleting " + f + " failed");
  }
} else {
  System.out.println("The file " + f + " doesn't exist");
}