Question

我正在制作一场生活游戏。

以下代码用于检查某个点有多少个邻居。

public int neighbours(int x, int y){
    int result = 0;
if(x!=0 && y!=0 && y!=getHeight() && x!= getLength()){
    if (life[x - 1][y + 1] == 1)
        result++;
    else if (life[x][y + 1] == 1)
        result++;
    else if (life[x + 1][y + 1] == 1)
        result++;
    else if (life[x + 1][y] == 1)
        result++;
    else if (life[x + 1][y - 1] == 1)
        result++;
    else if (life[x][y - 1] == 1)
        result++;
    else if (life[x - 1][y - 1] == 1)
        result++;
    else if (life[x - 1][y] == 1)
        result++;
} else if(x==0 && y==0){
    if (life[x][y + 1] == 1)
        result++;
    else if (life[x + 1][y + 1] == 1)
        result++;
    else if (life[x + 1][y] == 1)
        result++;
}
else if(x==0 && y==getHeight()){
    if (life[x + 1][y] == 1)
        result++;
    else if (life[x + 1][y - 1] == 1)
        result++;
    else if (life[x][y - 1] == 1)
        result++;
}
else if(y==getHeight() && x==getLength()){
    if (life[x][y - 1] == 1)
        result++;
    else if (life[x - 1][y - 1] == 1)
        result++;
    else if (life[x - 1][y] == 1)
        result++;
}
else if(y==0 && x==getLength()){
    if (life[x - 1][y + 1] == 1)
        result++;
    else if (life[x][y + 1] == 1)
        result++;
    else if (life[x - 1][y] == 1)
        result++;
}
else if (x==0){
    if (life[x][y + 1] == 1)
        result++;
    else if (life[x + 1][y + 1] == 1)
        result++;
    else if (life[x + 1][y] == 1)
        result++;
    else if (life[x + 1][y - 1] == 1)
        result++;
    else if (life[x][y - 1] == 1)
        result++;
}
else if(y==getHeight()){
    if (life[x + 1][y] == 1)
        result++;
    else if (life[x + 1][y - 1] == 1)
        result++;
    else if (life[x][y - 1] == 1)
        result++;
    else if (life[x - 1][y - 1] == 1)
        result++;
    else if (life[x - 1][y] == 1)
        result++;
}
else if(x==getLength()){
    if (life[x - 1][y + 1] == 1)
        result++;
    else if (life[x][y + 1] == 1)
        result++;
    else if (life[x][y - 1] == 1)
        result++;
    else if (life[x - 1][y - 1] == 1)
        result++;
    else if (life[x - 1][y] == 1)
        result++;
}
else if(y==0 && x!=getLength() && x!=0){
    if (life[x - 1][y + 1] == 1)
        result++;
    else if (life[x][y + 1] == 1)
        result++;
    else if (life[x + 1][y + 1] == 1)
        result++;
    else if (life[x + 1][y] == 1)
        result++;
    else if (life[x - 1][y] == 1)
        result++;
}
    return result;
}

正如您所看到的，我试图解决所有异常，但程序一直给我以下错误：

Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException: 30
at LifeGrid.neighbours(LifeGrid.java:165)
at LifeGrid.run(LifeGrid.java:179)
at TestLife.main(TestLife.java:15)

当我处理所有可能的异常时，你们有没有想过为什么仍然会发生越界异常。

Answer 1

你需要检查＆lt; getHeight / Width（），而不是==。如果它是== getHeight或getWidth，它将超出界限。

Answer 2

您对y == getHeight()的检查需要y == getHeight() - 1，因为这是您在董事会最底层时所拥有的价值。此外，您对x == getLength()的检查必须为x == getLength() - 1，因为这是您在董事会右侧边缘时所拥有的价值。

用java创建生活游戏

2 个答案: