Best practices regarding equals: to overload or not to overload?

Question

Consider the following snippet:

import java.util.*;
public class EqualsOverload {
    public static void main(String[] args) {
        class Thing {
                 


        

Answer 1

Let me share an example of "buggy code" with Overloaded equals:

class A{
    private int val;

    public A(int i){
        this.val = i;
    }

    public boolean equals(A a){
        return a.val == this.val;
    }

    @Override
    public int hashCode() {
        return Objects.hashCode(this.val);
    }
}

public class TestOverloadEquals {

    public static void main(String[] args){
        A a1 = new A(1), a2 = new A(2);
        List list = new ArrayList<>();
        list.add(a1);
        list.add(a2);
        A a3 =  new A(1);

        System.out.println(list.contains(a3));
    }
}