创建三种方法，改变价值观？ java的

Question

我有一个java程序，我有点困难，非常感谢帮助。

• addMine方法（应将the_minefield的值（在元素thisCol，thisRow处）从EMPTY_SQUARE更改为MINE_SQUARE，并返回值true。）

-addMine方法（如果输入参数位于雷区的维度之外，则该方法不应更改类的状态，并返回false。）

-addMine方法（如果输入参数指示的方块上已有一个矿，那么该方法不应该改变类的状态，并返回false。）

-getValue方法（应该返回所请求的行和列的雷区的值。（此时，雷区中的值是MINE_SQUARE或EMPTY_SQUARE）。如果行和列位于雷区之外，则方法应该返回0。）

-addMinesToCorners（应该按照它说的做，增加4个地雷）

class MineFinderModel
{
public static int MINE_SQUARE = 10;
public static int EMPTY_SQUARE = 0;

int num_of_cols;
int num_of_rows;
int[][] the_minefield;

public  MineFinderModel(int n_cols, int n_rows)
{
    num_of_rows = n_rows;
    num_of_cols = n_cols;
    the_minefield = new int[num_of_cols][num_of_rows];
}

public boolean addMine(int thisCol, int thisRow)
{

    return false; // but you sometimes need to return true;
}
public int getValue(int thisCol, int thisRow)
{

    return 0; // but you need to return other numbers at times;
}
public void addMinesToCorners()
{
}

}

Answer 1

public boolean addMine(int thisCol, int thisRow)
{
    if(thisCol >= n_cols || thisRow >= n_rows)
        return false;
    if(the_minefield[thisCol][thisRow] == MINE_SQUARE)
        return false;
    the_minefield[thisCol][thisRow] = MINE_SQUARE;
    return true;
}
public int getValue(int thisCol, int thisRow)
{
    if(thisCol >= n_cols || thisRow >= n_rows)
        return 0;
    return the_minefield[thisCol][thisRow];
}
public void addMinesToCorners()
{
    the_minefield[0][0] = MINE_SQUARE;
    the_minefield[0][n_rows - 1] = MINE_SQUARE;
    the_minefield[n_cols - 1][0] = MINE_SQUARE;
    the_minefield[n_cols - 1][n_rows - 1] = MINE_SQUARE;
}

Answer 2

public void addMinesToCorners()
{
/*Adding mines to four corners*/
the_minefield[0]0]                = "Corner Mine1"
the_minefield[0][num_of_cols -1]  = "Corner Mine2"
the_minefield[num_of_rows-1][0]   = "Corner Mine2"
the_minefield[num_of_rows -1][num_of_cols -1]  = "Corner Mine2"
}