@Override public boolean equals(Object obj) { if (obj instanceof MyLine) { MyLine otherLine = (MyLine) obj; double length1 = Math.pow(this.getEndX() - this.getStartX(), 2) + Math.pow(this.getEndY() - this.getStartY(), 2); double length2 = Math.pow(otherLine.getEndX() - otherLine.getStartX(), 2) + Math.pow(otherLine.getEndY() - otherLine.getStartY(), 2); return length1 == length2; } return false; }