CalendarEditor.java

import java.io.File;
import java.util.ArrayList;
public class CalendarEditor{
    private State currentState;
    private File appointmentFile;
    private ArrayList appointments = new ArrayList();
    private static final String DEFAULT_APPOINTMENT_FILE = "appointments.ser";
    
    public CalendarEditor(){
        this(DEFAULT_APPOINTMENT_FILE);
    }
    public CalendarEditor(String appointmentFileName){
        appointmentFile = new File(appointmentFileName);
        try{
            appointments = (ArrayList)FileLoader.loadData(appointmentFile);
        }
        catch (ClassCastException exc){
            System.err.println("Unable to load information. The file does not contain a list of appointments.");
        }
        currentState = new CleanState();
    }
    
    public void save(){
        currentState.save();
    }
    
    public void edit(){
        currentState.edit();
    }
    
    private class DirtyState implements State{
        private State nextState;

        public DirtyState(State nextState){
            this.nextState = nextState;
        }
        
        public void save(){
            FileLoader.storeData(appointmentFile, appointments);
            currentState = nextState;
        }
        public void edit(){ }
    }
    
    private class CleanState implements State{
        private State nextState = new DirtyState(this);
        
        public void save(){ }
        public void edit(){ currentState = nextState; }
    }
    
    public ArrayList getAppointments(){
        return appointments;
    }
    
    public void addAppointment(Appointment appointment){
        if (!appointments.contains(appointment)){
            appointments.add(appointment);
        }
    }
    public void removeAppointment(Appointment appointment){
        appointments.remove(appointment);
    }
}