Scanner class refuses to work

Question

Hi, I am having a really big pain in the butt issue with java, (ive tried using eclipse, jgrasp and bluej, all giving me same error)
I am trying to read from a .dat file (which can easily be opened with wordpad or notepad to reveal contents)
I am using scanner class
Scanner key = new Scanner (new File ("file.dat"));
no matter what i do, i keep getting the same error message FileNotFound Exception, i have gotten java to print out the directory it is searching for, i have put the file into that directory and i am still getting nothing....ive have been at this for two days now, and it is driving me nuts, nothing is making sense and i have asked everyone i know, they say that is the code you need to use to get it to read.
P.S i have also tried
File abc = new File ("file.dat");
Scanner key = new Scanner (abc); same result
I even got a little hopeful and tried just plain old
Scanner key = new Scanner ("file.dat); and i get nada, same error, im wondering if anyone has seen this before.

Answer 1

public static void populate(){
Scanner keyb= new Scanner(new File("city.dat"));
for(int j=0;j<=18;j++){
     int x = keyb.nextInt();
     String abr=keyb.next();
     int h = convert(abr);
     String name=keyb.next();
     int pop=keyb.nextInt();
     int alt = keyb.nextInt();
     city[x]=new cities(name,pop,alt);
     }Error Message: Exception in thread "main" java.lang.Error: Unresolved compilation problems:
     Unhandled exception type FileNotFoundException
     Unhandled exception type FileNotFoundException
     at Main.populate(Main.java:45) Line 45 is Scanner keyb= new Scanner(new File("city.dat"));
     at Main.main(Main.java:34) Line 34 is a call to the populate method.