java - 如何使用 FTP 目录填充 JTree？

Question

我正在使用 FTP4j，我想用 FTP 服务器的根目录填充 JTree。我尝试过使用 FTP4j 的 currentDirectory() 方法，但只返回一个“/”，这没有用。我还尝试将 ftp://url 传递给初始化 JTree 的方法，但这也不起作用。这是我的第一个 Swing 程序，所以我有点不知道该去哪里。这是代码:

package net.emptybox.ui;

import java.awt.EventQueue;

import javax.swing.JFrame;
import net.miginfocom.swing.MigLayout;
import javax.swing.JButton;
import java.awt.event.ActionListener;
import java.awt.event.ActionEvent;
import javax.swing.JLabel;
import javax.swing.JTextField;
import java.awt.FlowLayout;
import java.awt.BorderLayout;
import javax.swing.BoxLayout;
import javax.swing.JSplitPane;
import javax.swing.JSeparator;
import javax.swing.JTree;
import javax.swing.JTextArea;
import java.awt.Component;
import java.io.File;

import net.emptybox.ui.FTP;

import javax.swing.Box;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.JScrollPane;
import javax.swing.ScrollPaneConstants;



public class GUI {

    static JFrame frame;
    static private JSplitPane splitPane;
    static private JLabel lblServer;
    static private JTextField serverField;
    static private JLabel lblPort;
    static private JTextField portField;
    static private JLabel lblUsername;
    static private JTextField usernameField;
    static private JLabel lblPassword;
    static private JTextField passwordField;
    static private JButton connectButton;
    static private JSeparator separator;
    static private JTextArea detailArea;
    static private JButton downloadButton;
    static private JButton uploadButton;
    static private Component horizontalGlue;
    static private JTextField fileField;
    static private JButton goButton;
    static private Component horizontalGlue_1;

    static FileSystemModel fileSystemModel;
    static JLabel consoleLabel;
    private static Component verticalGlue;
    private static JScrollPane scrollPane;
    static JTree fileTree;

    /**
     * Launch the application.
     */

    /**
     * Create the application.
     */
    public GUI() {
        initialize();
    }

    /**
     * Initialize the contents of the frame.
     */
    public static void initialize() {
        frame = new JFrame();
        frame.setBounds(100, 100, 648, 300);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.getContentPane().setLayout(new MigLayout("", "[grow]", "[][][][grow][]"));

        lblServer = new JLabel("Server:");
        frame.getContentPane().add(lblServer, "flowx,cell 0 0");

        consoleLabel = new JLabel("");
        frame.getContentPane().add(consoleLabel, "flowx,cell 0 1");

        separator = new JSeparator();
        frame.getContentPane().add(separator, "cell 0 2");

        splitPane = new JSplitPane();
        splitPane.setOneTouchExpandable(true);
        splitPane.setContinuousLayout(true);
        frame.getContentPane().add(splitPane, "cell 0 3,grow");

        detailArea = new JTextArea();
        detailArea.setEditable(false);
        splitPane.setRightComponent(detailArea);

        scrollPane = new JScrollPane();
        scrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
        splitPane.setLeftComponent(scrollPane);

        serverField = new JTextField();
        frame.getContentPane().add(serverField, "cell 0 0,growx");

        lblPort = new JLabel("Port:");
        frame.getContentPane().add(lblPort, "cell 0 0");

        portField = new JTextField();
        frame.getContentPane().add(portField, "cell 0 0,growx");

        lblUsername = new JLabel("Username:");
        frame.getContentPane().add(lblUsername, "cell 0 0");

        usernameField = new JTextField();
        frame.getContentPane().add(usernameField, "cell 0 0,growx");

        lblPassword = new JLabel("Password:");
        frame.getContentPane().add(lblPassword, "cell 0 0");

        passwordField = new JTextField();
        frame.getContentPane().add(passwordField, "cell 0 0,growx");


        connectButton = new JButton("Connect");
        frame.getContentPane().add(connectButton, "cell 0 0");

        if (serverField.getText() == null || usernameField.getText() == null || passwordField.getText() == null) {
            connectButton.disable();
        } else {
            connectButton.enable();
        }

        if (portField.getText() == null) {
            portField.setText("21");
        }

        connectButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {
                FTP.connect(serverField.getText(), portField.getText(), usernameField.getText(), passwordField.getText());
            }
        });

        downloadButton = new JButton("Download");
        frame.getContentPane().add(downloadButton, "flowx,cell 0 4");
        downloadButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {
            }
        });

        uploadButton = new JButton("Upload");
        frame.getContentPane().add(uploadButton, "cell 0 4");
        uploadButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {
            }
        });

        horizontalGlue_1 = Box.createHorizontalGlue();
        frame.getContentPane().add(horizontalGlue_1, "cell 0 4,growx");

        fileField = new JTextField();
        frame.getContentPane().add(fileField, "cell 0 4");
        fileField.setColumns(200);

        goButton = new JButton("Go");
        goButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent arg0) {
            }
        });
        frame.getContentPane().add(goButton, "cell 0 4");

        horizontalGlue = Box.createHorizontalGlue();
        frame.getContentPane().add(horizontalGlue, "cell 0 4,alignx leading");

        verticalGlue = Box.createVerticalGlue();
        frame.getContentPane().add(verticalGlue, "cell 0 1");
    }

    private String getFileDetails(File file) {
        if (file == null)
          return "";
        StringBuffer buffer = new StringBuffer();
        buffer.append("Name: " + file.getName() + "\n");
        buffer.append("Path: " + file.getPath() + "\n");
        buffer.append("Size: " + file.length() + "\n");
        return buffer.toString();
      }

    public static void populateTree(String directory) {
        fileSystemModel = new FileSystemModel(new File(directory));

        fileTree = new JTree(fileSystemModel);
        scrollPane.setViewportView(fileTree);
    }
}

当与服务器成功建立连接并且用户已登录时，另一个类将调用填充树。

Answer 1

您将想要创建自己的 TreeModel。

用户成功连接后，您需要查询站点以获取更多信息，默认实现中没有可用的模型可以完成您想要的操作，您必须为此工作;)

让我们从 FTP 端开始。

String current = ftpSite.getCurrentDirectory(); // Just in case you want to come back
ftpSite.changeDirectort("/"); // Move to the root directory
FPTFile[] fileList = ftpSite.list(); // Get the list of files.

现在，如何处理这件事取决于你自己。但基本上，我会构造一个 MutableTreeNode 作为根节点(对于 JTree)。

从那里您可以根据需要向根添加新的 (MutableTreeNode) 节点。

您可以查看http://www.jroller.com/Thierry/entry/swing_lazy_loading_in_a了解有关如何实现这一切的更多想法。