import javax.swing.JOptionPane;
import java.util.ArrayList;
import java.util.Comparator;
import java.util.StringTokenizer;
import java.util.Collections;
import java.io.BufferedReader;
import java.io.FileReader;
import java.io.IOException;
import java.util.Scanner;

public class Example4A {
    
    public Example4A() throws IOException {
        ArrayList<Person> people = new ArrayList<Person>();
        BufferedReader in = new BufferedReader(new FileReader("people.data"));
        Scanner fileScanner = new Scanner(in);
        while( fileScanner.hasNext() ) {
            Scanner s = new Scanner(fileScanner.nextLine());
            String idNumber = s.next();
            String first = s.next();
            String last = "";
            while( s.hasNext() ) {
                last += s.next() + " ";
            } // end while
            Person aPerson = new Person(idNumber,first,last);
            // add aPerson to the end of the ArrayList
            people.add(aPerson);
        } // end while
        // The Collections class has a static method sort.
        // sort takes an ArrayList paramenter
        // The objects in the ArrayList must be Comparable
        // The ArrayList is sorted according to the natural comparator
        Collections.sort(people);
        display(people,"The names in \"natural\" order are:\n");
        // The Collections class has a second static method sort.
        // This sort takes an ArrayList paramenter and a Comparator parameter
        // The ArrayList is sorted according to the Comparator
        Collections.sort(people,new NameLengthOrder());
        display(people,"The names in first name length order are:\n");
        Collections.sort(people,new idNumberOrder());
        display(people,"The names in idNumber order are:\n");
    } // end Example4A()
    
    public static void main(String[] args) throws IOException {
        new Example4A();
        System.exit(0);
    } // end main
    
    public void display(ArrayList a, String title) {
        String out = title + "\n";
        for( int i = 0; i < a.size(); i++ ) {
            // the toString() method is automatically called on
            // a.get(i) since we are concatenating to a String
            // the "correct" toString() method is called
            // because of polymorphism
            out += a.get(i) + "\n";
        } // end for
        JOptionPane.showMessageDialog(null,out);
    } // end display
    
    // Comparator is an interface with one method to implement, the compare method.
    // This class implements compare so the order is by first name length.
    class NameLengthOrder implements Comparator<Person> {
        public int compare(Person personA, Person personB) {
            int difference = personB.getFirstName().length() - personA.getFirstName().length();
            if( difference != 0 ) return difference;
            // if no difference in name length compare "naturally"
            return personA.compareTo((personB));
        } // end compare
    } // end NameLengthOrder
    
    // This class implements compare so the order is by idNumber.
    class idNumberOrder implements Comparator<Person> {
        public int compare(Person personA, Person personB) {
            return personA.getIdNumber().compareTo(personB.getIdNumber());
        } // end compare
    } // end idNumberOrder
    
} // end Example4A