DefaultTableModel setValueAt抛出ArrayIndexOutOfboundsException

Question

我的要求是在网格中显示StockQuote符号(流数据)。为此，我选择了JTable。

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingUtilities;
import javax.swing.Timer;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.table.DefaultTableModel;

public class Preethi {

    protected void initUI() {
        final Random random = new Random();

        final DefaultTableModel model = new DefaultTableModel(new String[] { "Id", "Name", "Desg", "Sal" }, 0);
        final JTable table = new JTable(model);
        table.setFillsViewportHeight(true);
        JFrame frame = new JFrame(Preethi.class.getSimpleName());
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        JScrollPane scrollpane = new JScrollPane(table);
        frame.add(scrollpane, BorderLayout.CENTER);
        frame.pack();
        frame.setVisible(true);

        Random ran = new Random(12);
        ran.nextFloat();

        String str = new String("sss");

        String[] socrates = {str, str, str };
        model.addRow(socrates);

        System.out.println(model.getRowCount());
        System.out.println(model.getColumnCount());

        model.setValueAt(new Object[]{"ewqeq","rtgre","gfdgd","mbmnb"}, 1, 4);
    }

    public static void main(String[] args) throws ClassNotFoundException, InstantiationException, IllegalAccessException,
            UnsupportedLookAndFeelException {
        UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        SwingUtilities.invokeLater(new Runnable() {

            @Override
            public void run() {
                new Preethi().initUI();
            }
        });
    }
}

Answer 1

您不能设置不存在的行的值。

DefaultTableModel有一个addRow

正如Jon所提到的，您不应该对数据对象使用静态方法和字段

Answer 2

model.setValueAt(new Object[]{"ewqeq","rtgre","gfdgd","mbmnb"}, 1, 4);

第一行不存在，因此您将按照MadProgrammer的建议获取ArrayIndexOutOfBoundsException.，使用addRow(..)方法并将您的对象传递给它。

示例：

model.addRow(new Object[]{"ewqeq","rtgre","gfdgd","mbmnb"});

更新：

您仅定义了4列，因此索引将从0到3。但您在setValueAt方法中指定了4。所以你的问题是一样的。将其更改为3。