TAD agenda

package Agenda;   // todo dentro del pack agenda

public class Contacto {
    String nombre;
    int ID;

    public Contacto (String nombre, int ID){
        this.nombre = nombre;
        this.ID = ID;
    }

    public String toString(){
        return (this.nombre+" "+this.ID);
    }

}

//####################################################################################################################################
//package Agenda;

import java.util.ArrayList;

public class Agenda {
    ArrayList<Contacto> agenda;

    public Agenda(){
        this.agenda = new ArrayList<Contacto>();
    }

    public Contacto tope(){
        return (this.agenda.get(this.agenda.size()-1));
    }

    public void quitar(){
        this.agenda.remove(this.agenda.size()-1);
    }
    public boolean vacio(){
        return( this.agenda.isEmpty());
    }

    public void agregar(Contacto c){
        this.agenda.add(c);
    }


    public void agregarOrd(Contacto c){
        if( (this.vacio()) || (this.tope().ID>c.ID) ){
            this.agregar(c);
        }
        else{
            ArrayList<Contacto> aux = new ArrayList<Contacto>();
            boolean ordenado = false;
            while (!ordenado){
                if (this.tope().ID > c.ID){
                    aux.add(this.tope());
                    this.quitar();              }
                else{
                    this.agregar(c);


                    while(!ordenado){
                        this.agregar(aux.remove(aux.size()-1));
                        if(aux.isEmpty()){
                            ordenado = true;
                        }
                    }
                }
            }
        }
    }

    public String toString (){

        String ordenados = "";
        for (int i = this.agenda.size()-1; i>=0;i--){
            ordenados += agenda.get(i)+" ";
        }
         return ordenados;
    }




}
//########################################################################################################################
//package Agenda;

public class Main {

    public static void main(String[] args) {

        Agenda agenda = new Agenda();

        Contacto a = new Contacto ("Jere", 92);
        Contacto b = new Contacto ("Luca", 23);
        Contacto c = new Contacto ("Joge", 21);

        agenda.agregarOrd(a);
        agenda.agregarOrd(b);
        agenda.agregarOrd(c);


        System.out.println(agenda.toString());
    }

}