if (that instanceof this && this instanceof that)
{
   //...
}
else
{
  return false;
}

result = (this.getX() == that.getX() && this.getY() == that.getY());

result = that.xEquals( getX() ) && that.yEquals( getY() );

result = that.equals( getX(), getY() );

@Override public boolean equals(Object other) {
    return other instanceof Point ? ((Point)other).equals( getX(), getY() ) : false;
}

result = that.canEqual( this ) && that.colorEquals( getColor() ) && super.equals( that );

    @Override public boolean equals(Object other) {
        boolean result = false;
 
        if (other instanceof ColoredPoint) {

    @Override public boolean canEqual(Object other) {
        return (other instanceof ColoredPoint);

    @Override public boolean equals(Object other) {
        boolean result = false;
        if( this.canEqual( other ) ) {
            ColoredPoint that = (ColoredPoint) other;
            result = that.colorEquals( getColor() ) && super.equals( that );
 
        }
        return result;
    }

    return this.canEqual( other ) ?
      ((ColoredPoint)other).colorEquals( getColor() ) && super.equals( that ) :
      false;

public final boolean equals(Object o) { return equalsImpl(o,true); }

protected boolean equalsImpl(Object o,boolean isFirstPass)
{
    // reject if not an object from the base class hierarchy 
    if (!(o instanceof Point))
        return false;
   	
    Point p = (Point) o;

    // delegate if it's the first pass/call of this method 
    // and the object belongs to one of the subclasses
    if (isFirstPass && !(p.getClass().isInstance(this)))
        return p.equalsImpl(this,false);

    // reached for all objects from the base class hierarchy
    // which classes just inherit Point.equalsImpl() method 
    return (x == p.x && y == p.y);
}

public class Point {
 
    private final int x;
    private final int y;
 
    // ................
 
    @Override public boolean equals(Object obj) {
        return (obj instanceof Point &&
                    ((Point)obj).fEquals(this));
    }
 
    protected boolean fEquals(Point obj) {
        return (this.x == obj.x && this.y == obj.y);
    }
 
    @Override public int hashCode() {
           // ................
}
 
public class ColoredPoint extends Point {
 
    private final Color color;
 
    // ................
 
    @Override public boolean equals(Object obj) {
        return (obj instanceof ColoredPoint &&
                    ((ColoredPoint)obj).fEquals(this));
    }
 
    protected boolean fEquals(ColoredPoint obj) {
        return (this.color.equals(obj.color) && super.fEquals(obj));
    }
 
    @Override protected boolean fEquals(Point obj) {
        return false;
    }
 
    @Override public int hashCode() {
           // ................
}

@Override
public boolean equals( Object other ) {
    Point that;
    return this == other || (
        canEqual( other ) && ( that = ( Point )other ).canEqual( this ) &&
        getX() == that.getX() && getY() == that.getY()
    );
}

@Override
public boolean equals( Object other ) {
    C cOther;
    return this == other || (
        eqPrereq( this, other ) && // for direct subclasses of Object
//      super.equals( other ) && // otherwise
        nullSafeEquals( this.getProp1(), ( cOther = ( ( C )other ) ).getProp1() ) &&
        nullSafeEquals( this.getProp2(), cOther.getProp2() ) && ...
    );
}

return oOther != null && getEqualsClass( oThis ).equals( getEqualsClass( oOther ) );

  public boolean equals (final Object obj) {
    if (this == obj) {
      return true;
    }
    if (obj == null) {
      return false;
    }
    if (this.getClass() != obj.getClass()) {
      return false;
    }
    final Point other = (Point) obj;
    if (this.x != other.x) {
      return false;
    }
    if (this.y != other.y) {
      return false;
    }
    return true;
  }

  public boolean equals (final Object obj) {
    if (this == obj) {
      return true;
    }
    if (!super.equals(obj)) {
      return false;
    }
    if (this.getClass() != obj.getClass()) {
      return false;
    }
    final ColoredPoint other = (ColoredPoint) obj;
    if (this.color == null) {
      if (other.color != null) {
        return false;
      }
    } else if (!this.color.equals(other.color)) {
      return false;
    }
    return true;
  }

...
    if (this.getClass() != obj.getClass()) {
      if (obj.getClass().isAssignableFrom(this.getClass())) {
        return obj.equals(this);
      }
      if (!this.getClass().isAssignableFrom(obj.getClass())) {
        return false;
      }
    }
...

@Override public boolean canEqual(Object other) {
        return (other instanceof this.getClass());
    }

    @Override public boolean equals(Object other) {
        boolean result = false;
        if (other instanceof ColoredPoint) {
            ColoredPoint that = (ColoredPoint) other;
            result = (this.color.equals(that.color) && super.equals(that));
        }
        else if (other instanceof Point) {
            Point that = (Point) other;
            result = that.equals(this);
        }
        return result;
    }

interface Point {
  int getX();
  int getY();
}
 
interface ColoredPoint extends Point {
  Color getColor();
}
 
// lombok annotations
@Getter
@AllArgsConstructor
// compare by own fields x, y
@EqualsAndHashCode(of = {"x", "y"})
class PointImpl implements Point {
    private final int x;
    privaet final int y;
}
 
@Getter
@AllArgsConstructor
// compare by own fields point, color
@EqualsAndHashCode(of = {"point", "color"})
class ColoredPointImpl implements ColoredPoint {
    private final Point point; // just delegate getX, getY to point
    private final Color color;
}