小编myr*_*ipe的帖子

我有以下代码:

public class Matrix<K, V> {
    private final List<K> colKeys;
    private final List<K> rowKeys;
    private final Map<K, Map<K, V>> matrix;

    public Matrix() {
        colKeys = new LinkedList<>();
        rowKeys = new LinkedList<>();
        matrix = new TreeMap<>();
    }

    ...

    public V getCell(K row, K col) {
        return matrix.get(row).get(col);
    }

    ...

}

我像这样在另一个类中访问它:

Matrix matrix = new Matrix<String, Double>();

...

for (String colKey : colKeys) {
    double sum = 0;
    int divider = 0;

    for (String rowKey : rowKeys) {
        if (matrix.containsCell(rowKey, colKey)) …