public class Main {
    public static void main(String[] args) {
        Piece piece = new Piece();
        Queen queen = new Queen();
        Position testPosition = new Position(3,7);
        if(queen.isValidMove(testPosition)){
            System.out.println("Yes, I can move there.");
        }
        else {
            System.out.println("Nope, can't do!");
        }
    }
}

public class Game {
    Piece [][] board;
    // Constructor creates an empty board
    Game(){
        board = new Piece[8][8];
    }
}

public class Position {
    int row;
    int column;
    // Constructor using row and column values
    Position(int r, int c){
        this.row = r;
        this.column = c;
    }
}

public class Piece {
    Position position;

    boolean isValidMove(Position newPosition){
        if(position.row>0 && position.column>0
                && position.row<8 && position.column<8){
            return true;
        }
        else{
            return false;
        }
    }
}

public class Queen extends Piece {
    int row;
    int column;
    boolean isValidMove(Position newPosition){
        if(newPosition.column == this.column || newPosition.row == this.row|| Math.abs(newPosition.column - this.column) == Math.abs(newPosition.row - this.row)){
            return true;
        }
        else{
            return false;
        }
    }
}

boolean isValidMove(Position newPosition){
    // combine super.isValidMove(newPosition) and your current code
}