Question

我正在用Java编写一个tic-tac-toe游戏来回顾一些Java概念并练习OOP。到目前为止，我有4个课程：Board，Player，Coordinate和Game。我在测试Board课时遇到了问题。板由一系列坐标组成。目前有Board的两个不同构造函数。采用单个Coordinate的构造函数主要用于测试目的。

Board.java

public class Board {

    private Coordinate squares;
    private Coordinate[] coordinateSet;

    public Board(Coordinate squares) {
        this.squares = squares;
    }

    public Board(Coordinate[] coordinateSet) {
        this.coordinateSet = coordinateSet;
    }

    public Coordinate getSquares() {
        return squares;
    }

    public Coordinate[] getCoordinates() {
        return coordinateSet;
    }

    public Coordinate getCoordinate(int i) {
        return coordinateSet[i];
    }
}

Coordinate.java

public class Coordinate {

    private int x;
    private int y;
    private int xFlag; // 0 if available, 1 if not available
    private int yFlag; // 0 if available, 1 if not available
    private boolean squareAvailability;

    public Coordinate(int x, int y, int xFlag, int yFlag) {
        this.x = x;
        this.y = y;
        this.xFlag = xFlag;
        this.yFlag = yFlag;
    }

    public int getXCoordinate() {
        return x;
    }

    public int getYCoordinate() {
        return y;
    }

    public int getXFlag() {
        return xFlag;
    }

    public int getYFlag() {
        return yFlag;
    }

    public void setXFlag() {
        if(xFlag == 0) {
            xFlag = 1;
        } else { }
    }

    public void setYFlag() {
        if(yFlag == 0) {
            yFlag = 1;
        } else { }
    }

    public void add(Coordinate coordinate) {
        // TODO Auto-generated method stub

    }

    public boolean isSquareAvailable(Coordinate coordinate) {
        if(coordinate.getXFlag() == 0) {
            if(coordinate.getYFlag() == 0) {
                squareAvailability = true;
            } else {
                squareAvailability = false;
            }
        } else {
            squareAvailability = false;
        }       

        return squareAvailability;
    }

}

BoardTest.java

import edu.learning.tictactoe.Board;
import edu.learning.tictactoe.Coordinate;

public class BoardTest {

    public static void main(String[] args) {
        Coordinate[] coordinates = new Coordinate[9];   
        Coordinate coordinate = new Coordinate(0, 0, 0, 0);
        for(int i = 0; i < 3; i++) {
            for(int j = 0; j < 3; j++) {
                coordinates[i + j] = new Coordinate(i, j, 0, 0);
            }
        }
        Board board = new Board(coordinate);
        System.out.println(board.getSquares().getXCoordinate());
        Board board2 = new Board(coordinates);
        System.out.println(board2.getCoordinates().getCoordinate(0).getXCoordinate()); // error
    }
}

我在IDE BoardTest.java的最后一行Cannot invoke getCoordinate(int) on the array type Coordinate[]收到错误。问题是我试图从Coordinate个对象中返回一个Coordinate对象，这是不可能的（？）那么如何从一个Coordinate返回一个Coordinate数组//Code For Generate Certificate byte[] userCERT = (byte[])attrs.get("userCertificate").get(); ByteArrayInputStream bais = new ByteArrayInputStream( (userCERT)) ; CertificateFactory cf = CertificateFactory.getInstance("X.509"); X509Certificate cert = (X509Certificate)cf.generateCertificate(bais); s？

Answer 1

board.getCoordinates()返回一个数组，编译器错误告诉您该数组没有方法getCoordinate(int)。

简单写一下

board.getCoordinate(0).getXCoordinate()

如果你想通过你可以编写的数组访问坐标

board.getCoordinates()[0].getXCoordinate()

Java：封装和对象数组

1 个答案: