51.
@Override
public boolean equals(Object object) {
if (object instanceof A) {
A other = (A) object;
return Objects.equals(x, other.getX())
&& Objects.equals(y, other.getY());
}
return false;
}
@Override
public int hashCode() {
return Objects.hash(x, y);
}
A a1 = new A("hello", "world");
A a2 = new A("hello", "world");
assertTrue(a1.equals(a2)); // ← trueになる