Question

I am using FTP4j and I want to populate a JTree with the root directory of an FTP server. I’ve tried using FTP4j’s currentDirectory() method, but that only returns a “/” which isn’t useful. I’ve also tried passing the ftp:// url to a method that initializes the JTree, which doesn’t work either. This is my first Swing program so I’m kind of stumped on where to go. Here is the code:

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);
    }
}

Populate tree is called by another class when a connection is successfully established with the server and the user has logged in.

Answer 1

You’re going to want to create your own TreeModel.

Once the user has connected successfully, you’ll need to query the site for more information, there are no models available in the default implementation that will do what you want, you’re going have to work for it 😉

Let’s start with the FTP side.

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.

Now, how you go about this comes down to you. But basically, I would construct a MutableTreeNode as the root node (for the JTree).

From there you can add new (MutableTreeNode) nodes to the root as you need.

You could check out http://www.jroller.com/Thierry/entry/swing_lazy_loading_in_a for some more ideas on how to achieve all this.