import java.awt.BorderLayout;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.File;

import javax.swing.ButtonGroup;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JRadioButton;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.event.TreeExpansionEvent;
import javax.swing.event.TreeExpansionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreePath;

public class DateiBaum {

    public final static int SHOW_ALL = 0;
    public final static int SHOW_HIDDEN = 1;
    public final static int SHOW_VISIBLE = -1;

    private int showType = SHOW_VISIBLE;

    public DateiBaum(String path) {
        initGUI(path);
    }
    
    private void initGUI(String path) {
        JTree tree = new JTree(createModel(path));
        tree.addTreeExpansionListener(new TreeExpansionListener() {

            public void treeExpanded(TreeExpansionEvent event) {
                TreePath path = event.getPath();
                FNode node = (FNode) path.getLastPathComponent();
                DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
                node.addFiles(showType);
                model.nodeStructureChanged(node);
            }

            public void treeCollapsed(TreeExpansionEvent event) {
            }
        });
        JScrollPane sPane = new JScrollPane(tree);
        JFrame frame = new JFrame("Datei-Browser");
        frame.add(sPane, BorderLayout.CENTER);
        frame.add(createButtPanel(tree, path), BorderLayout.SOUTH);

        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    private DefaultTreeModel createModel(String path) {
        File root = new File(path);
        FNode rootNode = new FNode(root);
        rootNode.addFiles(showType);
        return new DefaultTreeModel(rootNode);
    }

    private JPanel createButtPanel(JTree tree, String path) {
        JPanel panel = new JPanel(new FlowLayout());
        JRadioButton allButt = new JRadioButton("Alle");
        allButt.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                showType = SHOW_ALL;
                tree.setModel(createModel(path));
            }
        });
        JRadioButton hiddenButt = new JRadioButton("Versteckt");
        hiddenButt.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                showType = SHOW_HIDDEN;
                tree.setModel(createModel(path));
            }
        });
        JRadioButton visibleButt = new JRadioButton("Sichtbar", true);
        visibleButt.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                showType = SHOW_VISIBLE;
                tree.setModel(createModel(path));
            }
        });
        ButtonGroup group = new ButtonGroup();
        group.add(allButt);
        group.add(hiddenButt);
        group.add(visibleButt);
        panel.add(allButt);
        panel.add(hiddenButt);
        panel.add(visibleButt);
        return panel;
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() -> new DateiBaum(System.getProperty("user.home")));
    }
}

class FNode extends DefaultMutableTreeNode {

    public FNode(File file) {
        setUserObject(file);
    }

    public File getFile() {
        return (File) getUserObject();
    }

    public boolean getAllowsChildren() {
        return getFile().isDirectory();
    }

    public boolean isLeaf() {
        return !getFile().isDirectory();
    }

    public String toString() {
        return getFile().getName();
    }

    public void addFiles(int showHidden) {
        File[] files = getFile().listFiles();
        for (File f : files) {
            if (showHidden == DateiBaum.SHOW_HIDDEN) {
                if (f.isHidden())
                    this.add(new FNode(f));
            } else if (showHidden == DateiBaum.SHOW_VISIBLE) {
                if (!f.isHidden())
                    this.add(new FNode(f));
            } else {
                this.add(new FNode(f));
            }
        }
    }
}