I am working on a dummy hospital database. I have an ArrayList that has the combination of all possible times that a doctor can theoretically hold an appointment, and another ArrayList that holds actual registered appointments.

Availability {
  int doctorid;
  String specialty;
  Date date;
  int order_of_appointment;
}
//////////

ArrayList<Availability> allTimes;

ArrayList<Availability> busyTimes;

What I want to accomplish is finding the times where doctors are free. Which is the result of (allTimes - busyTimes)

I tried using allTimes.removeAll(busyTimes) but it didn't remove anything.

I made sure that I am overriding the equals() method in the Availability class but it still doesn't remove anything.

@Override
public boolean equals(Object o) {
  if (this == o) return true;
  if (!(o instanceof Availability)) return false;   
  Availability that = (Availability) o;
  return doctorid == that.doctorid &&
      order_of_appointment == that.order_of_appointment &&
      Objects.equals(specialty, that.specialty) &&
      Objects.equals(date, that.date);
} 

Output:

1. busyTimes = [Availability{doctorid=1, specialty='internal medicine', date=2021-11-02, order_of_appointment=2} ]

2. allTimes = [Availability{doctorid=1, specialty='internal medicine', date=2021-11-02, order_of_appointment=1} , Availability{doctorid=1, specialty='internal medicine', date=2021-11-02, order_of_appointment=2} , Availability{doctorid=1, specialty='internal medicine', date=2021-11-02, order_of_appointment=3}]

3. The output I get for freeTimes is identical to allTimes even though I'm expecting it to remove the appointment with order_of_appointment==2.

I am totally clueless on what might be causing this. Any help would be appreciated. Thanks in advance!

CodePudding user response：

You don't show how are you creating the array, or how are you adding the elements.

I did a simple program with ArrayLists and works as expected:

import java.util.*;

class A {
  int id;
  A(int id) {
    this.id = id;
  }

  @Override
  public boolean equals(Object o) {
    return o instanceof A && this.id == ((A)o).id;
  }
  public String toString() {
    return String.format("A{id:%s}", id);
  }

  public static void main(String ... args) {
    List<A> a = new ArrayList<A>(Arrays.asList(new A(1), new A(2)));
    List<A> b = new ArrayList<A>(Arrays.asList(new A(2), new A(3)));
    a.removeAll(b);
    System.out.println(a);
  }
}

Output:

[A{id:1}]

CodePudding user response：

You need to override equals(Object obj) method in Availability class with your comparison logic.

I implemented it. please check.

import java.util.Date;

public class Availability {

    private int doctorId;
    private String specialty;
    private Date date;
    private int orderOfAppointment;

    public Availability() {
        super();        
    }

    public Availability(int doctorId, String specialty, Date date, int orderOfAppointment) {
        super();
        this.doctorId = doctorId;
        this.specialty = specialty;
        this.date = date;
        this.orderOfAppointment = orderOfAppointment;
    }

    public int getDoctorId() {
        return doctorId;
    }

    public void setDoctorId(int doctorId) {
        this.doctorId = doctorId;
    }

    public String getSpecialty() {
        return specialty;
    }

    public void setSpecialty(String specialty) {
        this.specialty = specialty;
    }

    public Date getDate() {
        return date;
    }

    public void setDate(Date date) {
        this.date = date;
    }

    public int getOrderOfAppointment() {
        return orderOfAppointment;
    }

    public void setOrderOfAppointment(int orderOfAppointment) {
        this.orderOfAppointment = orderOfAppointment;
    }

    @Override
    public String toString() {
        return "Availability  [doctorId="   doctorId   ", specialty="   specialty   ", date="   date
                  ", orderOfAppointment="   orderOfAppointment   "]";
    }

    @Override
    public boolean equals(Object obj) {
        boolean returnVal = false;
        Availability busyslote = (Availability) obj;
        if (this.doctorId == busyslote.doctorId && this.orderOfAppointment == busyslote.orderOfAppointment
                && this.specialty.equalsIgnoreCase(busyslote.specialty) && this.date.equals(busyslote.date)) {
            returnVal = true;
        } else {
            returnVal = false;
        }

        return returnVal;
    }
}

import java.util.ArrayList;
import java.util.Date;
import java.util.List;

public class AppointmentMain {

    public static void main(String[] args) {

        List<Availability> allAppointment = new ArrayList<>();
        List<Availability> attenedAppointment = new ArrayList<>();

        Availability obj1 = new Availability(1, "Internal Medicine", new Date(), 1);
        Availability obj2 = new Availability(1, "Internal Medicine", new Date(), 2);
        Availability obj3 = new Availability(1, "Internal Medicine", new Date(), 3);

        allAppointment.add(obj1);
        allAppointment.add(obj2);
        allAppointment.add(obj3);

        Availability obj4 = new Availability(1, "Internal Medicine", new Date(), 3);

        attenedAppointment.add(obj4);

        System.out.println("Befour count :"   allAppointment.size());
        allAppointment.removeAll(attenedAppointment);
        System.out.println("After count :"   allAppointment.size());
    }
}