Java 为数组单元格赋值

Question

我有 class Mappa 和 subclass MappaFermi 具有数组属性 Sector 扇区，数组的每个单元格都应该有一个名称，在 class 构造函数我在命名它们时没有遇到任何问题（所有测试都成功），但是在 subclass 构造函数中我得到 ArrayIndexOutOfBoundsException: 14 当尝试运行一个 NotNull 断言时。我将数组设置为受保护的，因此我可以在 subclass.

中使用它

public class Mappa {
    private Name mappaName;
    protected Sector [][] sector;
    private int Matrix [][];
    private static final int X=23;
    private static final int Y=14;
    public Mappa (Name mappaName){
        this.mappaName=mappaName;
        sector = new Settore[X][Y];
        for (int i=0; i < X; i++){
            for (int j=0; j<Y; j++) {
                sector[i][j] = new Settore (i,j);
            }
        }
        Matrix = new int[23][14];
        if(mappaName==Name.FERMI){
            sector[10][8]=new Alieni(10,8);
            sector[10][9]=new Umani(10,9);
        }
        if(mappaName==Name.GALILEI||mappaName==Name.GALVANI){
            sector[10][5]=new Alieni(10,5);//i have run all tests and it was successful
            sector[10][7]=new Umani(10,7);
        }
    }
}
public class MappaFermi extends Mappa {
    public MappaFermi() {
        super(null);
        new Mappa(Name.FERMI);
        setMatrix(new int[][]{
                        {0,0,0,0,0,0,0,0,0,3,0,0,0,3,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,0,1,0,2,0,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,2,1,2,1,2,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,1,2,2,2,1,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,3,0,1,0,3,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,1,0,0,1,0,0,1,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,2,1,0,1,0,2,1,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,1,1,1,1,1,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,2,0,0,0,0,0,1,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,1,1,1,0,0,0,1,2,1,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,1,0,1,1,1,1,1,0,2,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,2,1,0,1,0,2,1,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,0,2,0,1,0,0,0,0,0,0,0,0,0,0},
                        {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0}});
        for (int i=0; i < 14; i++){
            for (int j=0; j<23; j++){
                if (getMatrix()[i][j]==1){
                    sector[i][j]=new Sicuro(i,j);//this is where i get the error, if i only write `new Sicuro(i,j);` it runs successfully but i'm not storing the value in the cell of the array
                }
                else {
                    if (getMatrix()[i][j]==2){
                        sector[i][j]=new Pericoloso(i,j);   
                    }
                    else {
                        if (getMatrix()[i][j]==3){
                            sector[i][j]=new Scialuppa(i,j);
                        }
                    }
                }
            }
        }
        }


    }
public class MappaFermiTest {

    @Test
    public void testMappaFermi() {
        Mappa mappa = new MappaFermi();
        assertNotNull(mappa);
    }

}

Answer 1

扇区的尺寸为 [23][14]，但您正尝试通过迭代 [i in (0..14)]``[j in (0..23)] 对其进行初始化。您应该像这样初始化它：sector = new Settore[Y][X]; 或反转 X 和 Y 值。

Answer 2

反转下面的循环语句

for (int i=0; i < 14; i++){
            for (int j=0; j<23; j++){

和

for (int i=0; i < 23; i++){
            for (int j=0; j<14; j++){

因为 Array 扇区的维度是 [23][14]; 即 23 Rows and 14 Columns 。所以这就是为什么你需要分别遍历所有行和它们的列

Java 为数组单元格赋值

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