java中文件浏览对话框中怎么过滤文件类型

发布网友发布时间：2022-05-01 13:09

共2个回答

热心网友时间：2023-07-29 05:13

JFileChooser chooser = new JFileChooser();
FileNameExtensionFilter filter = new FileNameExtensionFilter(
"JPG & GIF Images", "jpg", "gif");
chooser.setFileFilter(filter);
int returnVal = chooser.showOpenDialog(parent);
if(returnVal == JFileChooser.APPROVE_OPTION) {
System.out.println("You chose to open this file: " +
chooser.getSelectedFile().getName());
}
JFileChooser就可以实现文件选择，但是只显示指定的文件类型的过滤类FileNameExtensionFilter只是JDK1.6版本里的，JDK1.4及其以下是没有的，如果想在JDK1.4里实现过滤，可以去1.6版本里找到该源码，自己编译使用

热心网友时间：2023-07-29 05:13

代码如下:
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 李钟尉
*/
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("显示指定类型的文件");
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("选择文件夹");
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("文件夹");
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("输入指定文件扩展名称：");
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[] {"文件名称", "文件大小","修改日期" }) {
/**
*
*/
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;
}
}