java - 从外部文件获取并显示在 JTable 中

Question

有人可以告诉我如何修改下面的程序吗？程序的数据通过 object[][] 传递 - 而不是仅给出应在表中打印数据的文件名。

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import java.awt.Dimension;
import java.awt.GridLayout;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

public class SimpleTableDemo extends JPanel {
private boolean DEBUG = false;

public SimpleTableDemo() {                                              
    super(new GridLayout(1,0));

    String[] columnNames = {"First Name",
                            "Last Name",
                            "Sport",
                            "# of Years",
                            "Vegetarian"};

    Object[][] data = {
    {"Kathy", "Smith",
     "Snowboarding", new Integer(5), new Boolean(false)},
    {"John", "Doe",
     "Rowing", new Integer(3), new Boolean(true)},
    {"Sue", "Black",
     "Knitting", new Integer(2), new Boolean(false)},
    {"Jane", "White",
     "Speed reading", new Integer(20), new Boolean(true)},
    {"Joe", "Brown",
     "Pool", new Integer(10), new Boolean(false)}
    };

    final JTable table = new JTable(data, columnNames);
    table.setPreferredScrollableViewportSize(new Dimension(500, 70));
    table.setFillsViewportHeight(true);

    if (DEBUG) {
        table.addMouseListener(new MouseAdapter() {
            public void mouseClicked(MouseEvent e) {
                printDebugData(table);
            }
        });
    }

    //Create the scroll pane and add the table to it.
    JScrollPane scrollPane = new JScrollPane(table);

    //Add the scroll pane to this panel.
    add(scrollPane);
}

private void printDebugData(JTable table) {
    int numRows = table.getRowCount();
    int numCols = table.getColumnCount();
    javax.swing.table.TableModel model = table.getModel();

    System.out.println("Value of data: ");
    for (int i=0; i < numRows; i++) {
        System.out.print("    row " + i + ":");
        for (int j=0; j < numCols; j++) {
            System.out.print("  " + model.getValueAt(i, j));
        }
        System.out.println();
    }
    System.out.println("--------------------------");
}

/**
 * Create the GUI and show it.  For thread safety,
 * this method should be invoked from the
 * event-dispatching thread.
 */
private static void createAndShowGUI() {
    //Create and set up the window.
    JFrame frame = new JFrame("SimpleTableDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //Create and set up the content pane.
    SimpleTableDemo newContentPane = new SimpleTableDemo();
    newContentPane.setOpaque(true); //content panes must be opaque
    frame.setContentPane(newContentPane);

    //Display the window.
    frame.pack();
    frame.setVisible(true);
}

public static void main(String[] args) {
    //Schedule a job for the event-dispatching thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
        public void run() {
            createAndShowGUI();
        }
    });
}
}

Answer 1

如果我理解问题正确，您可以将 Object[][] 数据替换为如下内容:

    String line;
    ArrayList<String[]> toData = new ArrayList<String[]>();
    File file = new File("\\file path");
    try{
        BufferedReader reader = new BufferedReader(new FileReader(file));
        while ((line = reader.readLine()) != null) {
            String[] lineElements = line.split(",");
            toData.add(lineElements);
        }
    }catch (Exception ex){
        ex.printStackTrace();
        System.out.println("File not found");
    }
    String[][] data = new String[toData.size()][];
    int index = 0;
    for(String[] a: toData){
        data[index]=a;
        index++;
    }

在此示例中，如果文件中的数据格式为:名字，姓氏，运动，是素食主义者。不过，您可以轻松更改它，但请记住还要更改 line.split() 中括号中的符号。

编辑:我不完全明白你想要实现什么，但我会这样做:

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.*;
import java.util.ArrayList;

public class Project {
    private JScrollPane scrollPane;
    private JFrame frame;
    private JTable table;

    public static void main (String[] args){
        Project project = new Project();
        project.createGUI();
    }

    public void createGUI(){
        frame = new JFrame();

        scrollPane = new JScrollPane();
        JPanel panel = new JPanel();
        JButton open = new JButton("Open");
        open.addActionListener(new OpenListener());
        JButton submit = new JButton("Submit");
        submit.addActionListener(new SubmitListener());
        JButton cancel = new JButton("Cancel");
        cancel.addActionListener(new CancelListener());
        panel.add(open);
        panel.add(submit);
        panel.add(cancel);

        frame.getContentPane().add(BorderLayout.CENTER,scrollPane);
        frame.getContentPane().add(BorderLayout.SOUTH,panel);


        frame.setSize(500,500);
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        frame.setVisible(true);
    }
    public void createAndDisplayList(String[][] data){
        String[] columnNames = {"First Name","Last Name","Sport","# of Years","Vegetarian"};
        table = new JTable(data, columnNames);
        frame.setVisible(false);
        frame.remove(scrollPane);
        scrollPane = new JScrollPane(table);
        frame.getContentPane().add(BorderLayout.CENTER,scrollPane);
        frame.revalidate();
        frame.setVisible(true);
    }
    private class OpenListener implements ActionListener {
        @Override
        public void actionPerformed(ActionEvent e) {
            JFileChooser fileChooser = new JFileChooser();
            String line;
            ArrayList<String[]> toData = new ArrayList<String[]>();
            fileChooser.showOpenDialog(frame);
            try{
                BufferedReader reader = new BufferedReader(new FileReader(fileChooser.getSelectedFile()));
                while ((line = reader.readLine()) != null) {
                    String[] lineElements = line.split(",");
                    toData.add(lineElements);
                }
                reader.close();
            }catch (Exception ex){
                ex.printStackTrace();
                JOptionPane.showMessageDialog(frame, "File not found", "Error", JOptionPane.ERROR_MESSAGE);
            }
            String[][] data = new String[toData.size()][];
            int index = 0;
            for(String[] a: toData){
                data[index]=a;
                index++;
            }
            createAndDisplayList(data);
        }
    }

    private class CancelListener implements ActionListener {
        @Override
        public void actionPerformed(ActionEvent e) {
            frame.remove(scrollPane);
            scrollPane = new JScrollPane();
            frame.getContentPane().add(BorderLayout.CENTER,scrollPane);
            frame.revalidate();
            frame.setVisible(true);
        }
    }

    private class SubmitListener implements ActionListener {
        @Override
        public void actionPerformed(ActionEvent e) {
            JFileChooser fileChooser = new JFileChooser();
            fileChooser.showSaveDialog(frame);
            try{
                BufferedWriter bufferedWriter = new BufferedWriter(new FileWriter(fileChooser.getSelectedFile()));
                for(int i = 0; i<table.getRowCount(); i++){
                    for(int j = 0; j<table.getColumnCount(); j++){
                        System.out.println(i + "," + table.getRowCount());
                        bufferedWriter.write(table.getValueAt(i, j).toString() + ",");
                    }
                    bufferedWriter.newLine();
                }
                bufferedWriter.close();
            }catch (IOException ex){
                ex.printStackTrace();
                JOptionPane.showMessageDialog(frame,"File not found","Error",JOptionPane.ERROR_MESSAGE);
            }
        }
    }
}

但是请注意，这是一个原始且业余编写的代码，但它在某种程度上有效。您可以打开、更改内容和保存文件(提交)，但不能在表中添加行，您需要在 .txt 文件中执行此操作(但不能在文件末尾留任何空白)。不管怎样，我希望你能在这里找到有用的东西。