Print Total Number of Different Words (case sensitive) from a file

Question

**Edit after reviewing Tormod's answer and implementing his advice.

As the title states I'm attempting to print the total number of different words after receiving a file name from command line input. I receive the following message after attempting to compile the program:

Note: Project.java uses unchecked or unsafe operations. Note: Recompile with -Xlint:unchecked for details.

Here is my code. Any help is greatly appreciated:

import java.lang.*;
import java.util.*;
import java.io.*;

public class Project {

    public static void main(String[] args) throws IOException {

        File file = new File(args[0]);
        Scanner s = new Scanner(file);
        HashSet lib = new HashSet<>();

        try (Scanner sc = new Scanner(new FileInputStream(file))) {
            int count = 0;
            while(sc.hasNext()) {
                sc.next();
                count++;
            }
        System.out.println("The total number of word in the file is: " + count);
        }

    while (s.hasNext()) {

        String data = s.nextLine();
        String[] pieces = data.split("\\s+");

        for (int count = 0; count < pieces.length; count++)
        {
        if(!lib.contains(pieces[count])) {
            lib.add(pieces[count]);
            }
        }
    }
    System.out.print(lib.size());
}
}

Answer 1

I would implement it using a HashSet Add all the words, and read out the size. If you want to make it case insensitive just manipulate all the words to uppercase or something like that. this uses some memory but...

one problem you got with the algorithm is that you do only have one "words". it only holds the words at the same line. so you only count same words at the same line.

HashSet stores strings by their hash value, and thus stores one word only one time.

construction: HashSet lib = new HashSet<>();

inside the loop: if(!lib.contains(word)){lib.add(word);}

check the word count: lib.size()