// 创建文件选择器并设置为仅选择目录
JFileChooser directoryChooser = new JFileChooser();
// 只能选择目录
directoryChooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
directoryChooser.setDialogTitle("选择目录");

// 设置默认路径为桌面（可选）
File desktop = new File(System.getProperty("user.home"), "Desktop");
if (desktop.exists() && desktop.isDirectory()) {
    directoryChooser.setCurrentDirectory(desktop);
}

// 显示选择对话框
int result = directoryChooser.showOpenDialog(mainPanel);
if (result == JFileChooser.APPROVE_OPTION) {
    File outPathFile = directoryChooser.getSelectedFile();
    System.out.println(outPathFile.getAbsolutePath());
}

原文出处：/show_1GW1cvHOxa4q.html