class GridPosition { final int x; final int y; GridPosition(final int x, final int y) { this.x = x; this.y = y; } /* * This equals method is of deliberately narrow scope (only allows comparison with another GridPosition) to increase * readability. In general, one should provide a full implementation of Object.equals(Object obj) and a * corresponding implementation of Object.hashCode(). See * * https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#equals(java.lang.Object) * * and * * https://docs.oracle.com/javase/7/docs/api/java/lang/Object.html#hashCode() * * for more information. */ boolean equals(final GridPosition gridPosition) { return this.x == gridPosition.x && this.y == gridPosition.y; } }