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

/**
 * This class shows how you can read in from a file using a Scanner object. 
 * 
 * This class also shows how to handle a checked exception. A checked 
 * exception is an exception that you can typically anticipate and/or 
 * recover from. In Java, you are required to handle checked exceptions.
 * 
 * @author alchambers
 * @version sp18
 */
public class FileIO{

    /**
     * Uses a Scanner to read in from a file. This method throws
     * any I/O exceptions that occur when reading from the file.
     * 
     * @param filename The name of the file to be read 
     */
    private static void readWithScannerThrows(String filename) throws IOException{
        System.out.println("Here are the contents of the file:");
        File file = new File(filename);
        Scanner in = new Scanner(file);
        String line = "";
        while(in.hasNext()){
            line = in.nextLine(); // read in a line from file
            System.out.println(line); // print out the line
        }
        in.close();
    }    

    /**
     * Uses a Scanner to read in from a file. This method handles
     * any I/O exceptiosn that occur when reading from the file.
     * 
     * @param filename The name of the file to be read
     */
    private static void readWithScannerHandles(String filename){
        try{
            System.out.println("Here are the contents of the file:");
            File file = new File(filename);
            Scanner in = new Scanner(file);
            String line = "";
            while(in.hasNext()){
                line = in.nextLine(); // read in a line from file
                System.out.println(line); // print out the line
            }
            in.close();
        }
        catch(IOException e){
            System.err.println(e);
        }
    }

    private static void method2(String filename){
        readWithScannerHandles(filename);
    }

    private static void method1(String filename){
        method2(filename);
    }

    public static void main(String[] args) {
        method1("non existent file");
    }

}