java - 无法在同一类的对象上使用方法

Question

我正在实现一个 JFrame 类，它必须查看表并对其执行某些操作。该表有一个 AbstractTableModel，我已经在其上定义了一个要在 JFrame 类中使用的方法。但我无法做到这一点。 这里是代码:

必须查看 JTable 的 JFrame 类

public class CreaOrario extends JFrame {


public CreaOrario(int num) {
    initialize(num);
}

/**
 * Initialize the contents of the frame.
 */
private void initialize(final int semestre) {
    this.setSize(1150,650);
    this.setTitle("Creazione dell'Orario");
    this.setLocationRelativeTo(null);
    this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);


    TabellaOrario orarioEditabile = new TabellaOrario(semestre);
    this.getContentPane().add(orarioEditabile, BorderLayout.CENTER);

    final JTable table = orarioEditabile.getTable();
    //now I'd like to do: table.getLesson;
}
}

必须在 JFrame 中添加并包含表格的 JPanel 类:

public class TabellaOrario extends JPanel
{
private JTable table;

public TabellaOrario (int semestre)
{

    setLayout(new BoxLayout(this, BoxLayout.Y_AXIS)); 
    table = new JTable(new MyTableModel());
    table.setFillsViewportHeight(true);     
    table.setPreferredScrollableViewportSize(new Dimension(510, 350));
    JScrollPane jps = new JScrollPane(table);
    add(jps);
    add(new JScrollPane(table));
    table.setCellSelectionEnabled(true);
    table.setRowHeight(40);

}

public JTable getTable() {
    return table;
}
public class MyTableModel extends AbstractTableModel 
{   


private String[] columns = {"","Lunedì","Martedì", "Mercoledì", "Giovedì", "Venerdì", "Sabato"};


private Object [][] data = {{"8:30 - 9:30","","","","","",""},
        {"9:30 - 10:30","","","","","",""},
        {"10:30 - 11:30","","","","","",""},
        {"11:30 - 12:30","","","","","",""},
        {"12:30 - 13:30","","","","","",""},
        {"13:30 - 14:30","","","","","",""},
        {"14:30 - 15:30","","","","","",""},
        {"15:30 - 16:30","","","","","",""},
        {"16:30 - 17:30","","","","","",""}};



        @Override
        public int getColumnCount() {
            return columns.length;
        }

        @Override
        public int getRowCount() {
            return data.length;
        }

        @Override
        public String getColumnName(int col) {
            return columns[col];
        }

        @Override
        public Object getValueAt(int row, int col) {
            return data[row][col];

        }

        @Override
        public void setValueAt(Object aValue, int row, int col) {
            data[row][col] = aValue;
            fireTableCellUpdated(row, col);

            }

     }
        public String[] getLesson (int row, int column)
        {
            String value = (String) table.getValueAt(row, column);
            int start = value.indexOf("<b>");
            int end = value.indexOf("</b>");
            String insegnamento = value.substring(start + "<b>".length(), end);

            start = value.lastIndexOf("<b>");
            end = value.lastIndexOf("</b>");
            String aula = value.substring(start + "<b>".length(), end);

            return new String[] {insegnamento,aula};

        }
}
}

在 MyTableModel 类中，我定义了要在 CreaOrario 类中使用的方法 getLesson()。

但是，如果在MyTableModel中我编写table.getLesson()，则会显示一条消息错误，指出该方法 getLesson() 对于该类型未定义JTable。 为什么？ table 实际上是一个 TabellaOrario 对象，并以 MyTableModel 作为模型。 getLesson() 是为 MyTableModel 定义的，因此我希望 table.getLesson() 可以工作。

Answer 1

这是因为 table 被声明为 JTable 并且 getTable() 返回一个 JTable。您只需要进行类型转换，因为 JTable 中不存在 getLesson()。

您需要像这样调用 getLesson():

String[] lessons = ((TabellaOrario.MyTableModel)table.getModel()).getLesson();