Read File and Find Adjacent List & Matrix

/* Connections between nodes are given in the file
5
10
0,1
0,2
1,0
1,2
1,4
2,0
2,1
2,3
3,2
4,1
read it and find adjacent list and adjacent matrix */

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

public class AdjacentListMatrix {

    private static HashMap<String, ArrayList<String>> adjacentList;
    private static int numOfNodes;
    private static int numOfEdges;

    public static void main(String[] args) {
        adjacentList = new HashMap<>();
        readFile("Adjacent List.txt");
        System.out.println("\n* Adjacent List:");
        printAdjacentList();
        System.out.println("\n* Adjacent Matrix:");
        printAdjacentMatrix();
    }

    public static void readFile(String fileName) {
        try {
            File file = new File(fileName);
            Scanner scannedFile = new Scanner(file);

            numOfNodes = Integer.parseInt(scannedFile.nextLine());
            numOfEdges = Integer.parseInt(scannedFile.nextLine());

            String tempKey = "";
            ArrayList<String> tempList = new ArrayList<>();

            while(scannedFile.hasNextLine()) {
                String newLine = scannedFile.nextLine();
                String[] splittedLine = newLine.split(",");

                if (tempKey.equals("")) {
                    tempKey = splittedLine[0];
                    tempList.add(splittedLine[1]);
                }
                else if (tempKey.equals(splittedLine[0])) {
                    tempList.add(splittedLine[1]);
                }
                else if (!tempKey.equals(splittedLine[0])) {
                    adjacentList.put(tempKey, tempList);
                    tempKey = splittedLine[0];
                    tempList = new ArrayList<>();
                    tempList.add(splittedLine[1]);
                }

                if (!scannedFile.hasNextLine()) {
                    adjacentList.put(tempKey, tempList);
                }
            }

        }
        catch(FileNotFoundException ex) {
            ex.printStackTrace();
        }
    }

    public static void printAdjacentList() {
        for (String key : adjacentList.keySet()) {
            System.out.print(key + " : ");
            ArrayList<String> list = adjacentList.get(key);
            for (String val : list) {
                System.out.print(val + " ");
            }
            System.out.println();
        }
    }

    public static void printAdjacentMatrix() {
        for (int i = 0; i < numOfNodes; i++) {
            ArrayList<String> list = adjacentList.get(Integer.toString(i));
            for (int j = 0; j < numOfNodes; j++) {
                if (list.contains(Integer.toString(j)))
                    System.out.print("1 ");
                else System.out.print("0 ");
            }
            System.out.println();
        }
    }
}