实现：读取文件夹指定类型的文件，并显示到表格控件中。
应用：对于项目开发中的文件分类起到了抛砖引玉的作用。
效果图：
实现代码：
package com.lixiyu;import java.awt.BorderLayout;import java.awt.EventQueue;import java.awt.GridBagConstraints;import java.awt.GridBagLayout;import java.awt.Insets;import java.awt.event.ActionEvent;import java.awt.event.ActionListener;import java.io.File;import java.sql.Date;import javax.swing.JButton;import javax.swing.JFileChooser;import javax.swing.JFrame;import javax.swing.JLabel;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JTable;import javax.swing.JTextField;import javax.swing.border.EmptyBorder;import javax.swing.event.CaretEvent;import javax.swing.event.CaretListener;import javax.swing.table.DefaultTableModel;public class ListCustomTypeFile extends JFrame { /** * */ private static final long serialVersionUID = -6263975104443132420L; /** * 自定义扩展名过滤器 * * @author DylanLee */ private final class CustomFilter implements java.io.FileFilter { @Override public boolean accept(File pathname) { // 获取用户设置的指定扩展名 String extName = extNameField.getText(); if (extName == null || extName.isEmpty()) return false; if (!extName.startsWith("."))// 判断扩展名前缀 extName = "." + extName;// 完事扩展名前缀 extName = extName.toLowerCase(); // 判断扩展名与过滤文件名是否符合要求 if (pathname.getName().toLowerCase().endsWith(extName)) return true; return false; } } private JPanel contentPane; private JTextField extNameField; private JTable table; private File dir; private JLabel label; /** * Launch the application. */ public static void main(String[] args) { EventQueue.invokeLater(new Runnable() { public void run() { try { ListCustomTypeFile frame = new ListCustomTypeFile(); frame.setVisible(true); } catch (Exception e) { e.printStackTrace(); } } }); } /** * Create the frame. */ public ListCustomTypeFile() { setTitle("\u663E\u793A\u6307\u5B9A\u7C7B\u578B\u7684\u6587\u4EF6"); setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); setBounds(100, 100, 450, 300); contentPane = new JPanel(); contentPane.setBorder(new EmptyBorder(5, 5, 5, 5)); contentPane.setLayout(new BorderLayout(0, 0)); setContentPane(contentPane); JPanel panel = new JPanel(); contentPane.add(panel, BorderLayout.NORTH); GridBagLayout gbl_panel = new GridBagLayout(); gbl_panel.columnWidths = new int[] { 93, 54, 0 }; gbl_panel.rowHeights = new int[] { 23, 0, 0 }; gbl_panel.columnWeights = new double[] { 0.0, 1.0, Double.MIN_VALUE }; gbl_panel.rowWeights = new double[] { 0.0, 0.0, Double.MIN_VALUE }; panel.setLayout(gbl_panel); JButton button = new JButton("\u9009\u62E9\u6587\u4EF6\u5939"); button.addActionListener(new ActionListener() { public void actionPerformed(ActionEvent e) { do_button_actionPerformed(e); } }); GridBagConstraints gbc_button = new GridBagConstraints(); gbc_button.anchor = GridBagConstraints.NORTH; gbc_button.gridx = 0; gbc_button.gridy = 0; panel.add(button, gbc_button); label = new JLabel("\u6587\u4EF6\u5939"); GridBagConstraints gbc_label = new GridBagConstraints(); gbc_label.fill = GridBagConstraints.HORIZONTAL; gbc_label.gridx = 1; gbc_label.gridy = 0; panel.add(label, gbc_label); JLabel label_1 = new JLabel( "\u8F93\u5165\u6307\u5B9A\u6587\u4EF6\u6269\u5C55\u540D\u79F0\uFF1A"); GridBagConstraints gbc_label_1 = new GridBagConstraints(); gbc_label_1.anchor = GridBagConstraints.EAST; gbc_label_1.insets = new Insets(0, 0, 0, 5); gbc_label_1.gridx = 0; gbc_label_1.gridy = 1; panel.add(label_1, gbc_label_1); extNameField = new JTextField(); extNameField.addCaretListener(new CaretListener() { public void caretUpdate(CaretEvent e) { do_extNameField_caretUpdate(e); } }); extNameField.setText(".gif"); GridBagConstraints gbc_extNameField = new GridBagConstraints(); gbc_extNameField.insets = new Insets(0, 0, 5, 0); gbc_extNameField.fill = GridBagConstraints.HORIZONTAL; gbc_extNameField.gridx = 1; gbc_extNameField.gridy = 1; panel.add(extNameField, gbc_extNameField); extNameField.setColumns(10); JScrollPane scrollPane = new JScrollPane(); contentPane.add(scrollPane, BorderLayout.CENTER); table = new JTable(); table.setAutoResizeMode(JTable.AUTO_RESIZE_OFF); table.setModel(new DefaultTableModel(new Object[][] {}, new String[] { "\u6587\u4EF6\u540D\u79F0", "\u6587\u4EF6\u5927\u5C0F", "\u4FEE\u6539\u65E5\u671F" }) { /** * */ private static final long serialVersionUID = 5274214559103654856L; boolean[] columnEditables = new boolean[] { false, false, false }; public boolean isCellEditable(int row, int column) { return columnEditables[column]; } }); table.getColumnModel().getColumn(0).setPreferredWidth(220); table.getColumnModel().getColumn(1).setPreferredWidth(85); table.getColumnModel().getColumn(2).setPreferredWidth(110); scrollPane.setViewportView(table); } /** * 选择文件夹按钮的事件处理方法 * * @param e */ protected void do_button_actionPerformed(ActionEvent e) { JFileChooser chooser = new JFileChooser();// 创建文件选择器 // 设置选择器的过滤器 chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY); chooser.showDialog(this, null); dir = chooser.getSelectedFile(); getLabel().setText(dir.toString()); // 获取过滤后的符合条件的文件数组 listFiles(); } /** * 显示文件夹中的文件 */ private void listFiles() { if (dir == null) return; // 获取符合条件的文件数组 File[] files = dir.listFiles(new CustomFilter()); // 获取表格的数据模型 DefaultTableModel model = (DefaultTableModel) table.getModel(); model.setRowCount(0); for (File file : files) {// 遍历文件数组 // 创建表格行数据 Object[] row = { file.getName(), file.length(), new Date(file.lastModified()) }; model.addRow(row);// 添加行数据到表格模型 } } protected void do_extNameField_caretUpdate(CaretEvent e) { listFiles(); } protected JLabel getLabel() { return label; }}