jTable中两列数据的乘法

Question

我有一个小应用程序如下GUI OF APP

问题是我将从表列1,2中获取数据并将两个数据相乘并将答案打印到第3列一切正常但我没有得到最后一行结果并将异常抛给我关注working error

完整代码如下

import java.awt.EventQueue;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;
import javax.swing.JLabel;
import javax.swing.JSpinner;
import javax.swing.JButton;
import javax.swing.JTable;
import javax.swing.JScrollPane;
import javax.swing.table.DefaultTableModel;
import javax.swing.JTextField;
import javax.swing.UIManager;

import java.awt.event.ActionListener;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.Vector;
import java.awt.event.ActionEvent;
import javax.swing.JTextArea;

public class mU extends JFrame {

    private JPanel contentPane;
    private JTable table;
    private JTextField textField;
    Double l2;
    Double l4;
    Double d,d2;
    int hu;
    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    mU frame = new mU();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public mU() {
        try{    
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
        }
        catch(Exception w1){

        }  

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 486, 297);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);

        JLabel lblNumberOfMachines = new JLabel("Number of Machines");
        lblNumberOfMachines.setBounds(10, 11, 120, 14);
        contentPane.add(lblNumberOfMachines);

        JSpinner spinner = new JSpinner();
        spinner.setBounds(140, 8, 48, 20);
        contentPane.add(spinner);

        JScrollPane scrollPane = new JScrollPane();
        scrollPane.setBounds(208, 11, 252, 239);
        contentPane.add(scrollPane);

        table = new JTable();
        table.setRowSelectionAllowed(false);
        table.setModel(new DefaultTableModel(
            new Object[][] {
            },
            new String[] {
                "Machine", "N(1)", "N(0)", "Qan"
            }
        ));
        scrollPane.setViewportView(table);
        DefaultTableModel model = (DefaultTableModel) table.getModel();
        table.setModel(model);

        JLabel lblSum = new JLabel("Sum");
        lblSum.setBounds(10, 117, 46, 14);
        contentPane.add(lblSum);

        textField = new JTextField();
        textField.setBounds(39, 114, 105, 20);
        contentPane.add(textField);
        textField.setColumns(10);

        JButton btnNewButton = new JButton("Generate");
        btnNewButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                DefaultTableModel model = (DefaultTableModel) table.getModel();
                table.setModel(model);
                int hu=(Integer) spinner.getValue();
                for(int i=0;i<hu;i++) {
                    model.addRow(new Object[] {"M"+(i+1),"0","0",""});

                }
            }
        });

        btnNewButton.setBounds(10, 36, 77, 23);
        contentPane.add(btnNewButton);


        JButton btnClear = new JButton("CLEAR");
        btnClear.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                model.setRowCount(0);
            }
        });
        btnClear.setBounds(89, 36, 65, 23);
        contentPane.add(btnClear);

        JButton btnInitilize = new JButton("N");
        btnInitilize.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {

                for (int i=0; i<=model.getColumnCount(); i++) 
                {
                     Double d= Double.parseDouble((String) model.getValueAt(i,1));
                     Double d2= Double.parseDouble((String) model.getValueAt(i,2));
                    Double d3=d*d2;
                    model.setValueAt(d3,i,3);
                 }  

            }
        });
        btnInitilize.setBounds(10, 63, 46, 23);
        contentPane.add(btnInitilize);

    }
}

任何人都可以帮助我吗

Answer 1

在btnInitilize动作监听器中，行

for (int i=0; i<=model.getColumnCount(); i++)

应该是

for (int i=0; i<model.getRowCount(); i++)

根据您的请求，您的代码更改了一行。您没有经过测试，例外：

package mU;

import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSpinner;
import javax.swing.JTable;
import javax.swing.JTextField;
import javax.swing.UIManager;
import javax.swing.border.EmptyBorder;
import javax.swing.table.DefaultTableModel;

public class mU extends JFrame {

    private JPanel contentPane;
    private JTable table;
    private JTextField textField;
    Double l2;
    Double l4;
    Double d,d2;
    int hu;
    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
            public void run() {
                try {
                    mU frame = new mU();
                    frame.setVisible(true);
                } catch (Exception e) {
                    e.printStackTrace();
                }
            }
        });
    }

    /**
     * Create the frame.
     */
    public mU() {
        try{    
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
        }
        catch(Exception w1){

        }  

        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setBounds(100, 100, 486, 297);
        contentPane = new JPanel();
        contentPane.setBorder(new EmptyBorder(5, 5, 5, 5));
        setContentPane(contentPane);
        contentPane.setLayout(null);

        JLabel lblNumberOfMachines = new JLabel("Number of Machines");
        lblNumberOfMachines.setBounds(10, 11, 120, 14);
        contentPane.add(lblNumberOfMachines);

        final JSpinner spinner = new JSpinner();
        spinner.setBounds(140, 8, 48, 20);
        contentPane.add(spinner);

        JScrollPane scrollPane = new JScrollPane();
        scrollPane.setBounds(208, 11, 252, 239);
        contentPane.add(scrollPane);

        table = new JTable();
        table.setRowSelectionAllowed(false);
        table.setModel(new DefaultTableModel(
            new Object[][] {
            },
            new String[] {
                "Machine", "N(1)", "N(0)", "Qan"
            }
        ));
        scrollPane.setViewportView(table);
        final DefaultTableModel model = (DefaultTableModel) table.getModel();
        table.setModel(model);

        JLabel lblSum = new JLabel("Sum");
        lblSum.setBounds(10, 117, 46, 14);
        contentPane.add(lblSum);

        textField = new JTextField();
        textField.setBounds(39, 114, 105, 20);
        contentPane.add(textField);
        textField.setColumns(10);

        JButton btnNewButton = new JButton("Generate");
        btnNewButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                DefaultTableModel model = (DefaultTableModel) table.getModel();
                table.setModel(model);
                int hu=(Integer) spinner.getValue();
                for(int i=0;i<hu;i++) {
                    model.addRow(new Object[] {"M"+(i+1),"0","0",""});

                }
            }
        });

        btnNewButton.setBounds(10, 36, 77, 23);
        contentPane.add(btnNewButton);


        JButton btnClear = new JButton("CLEAR");
        btnClear.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                model.setRowCount(0);
            }
        });
        btnClear.setBounds(89, 36, 65, 23);
        contentPane.add(btnClear);

        JButton btnInitilize = new JButton("N");
        btnInitilize.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {

                for (int i=0; i<model.getRowCount(); i++) 
                {
                     Double d= Double.parseDouble((String) model.getValueAt(i,1));
                     Double d2= Double.parseDouble((String) model.getValueAt(i,2));
                    Double d3=d*d2;
                    model.setValueAt(d3,i,3);
                 }  

            }
        });
        btnInitilize.setBounds(10, 63, 46, 23);
        contentPane.add(btnInitilize);
        }
}