/**
 *定義資源管理器類，包括初始化，點擊tree和list事件的監聽，樹的展開與收縮監聽
 *調用FileNode.java構造目錄樹
 */
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.tree.*;
import java.awt.*;
import java.awt.event.*;
import java.io.File;
import java.util.EventObject;
import java.util.*;

public class Explorer extends JFrame implements TreeExpansionListener,TreeSelectionListener, ActionListener 
//資源管理器類實現：樹展開監聽器，選擇樹監聽器，列表的單擊動作監聽器
{
    final JTree tree = new JTree(createTreeModel());//定義樹型
    final JPanel list = new JPanel(new GridLayout(19,3));//定義列表
    final JSplitPane split;
    final JPanel jPanel1 = new JPanel(new BorderLayout());//添加面板
    final JLabel jLabel1 = new JLabel(" ");//記錄所選擇文件的路徑
    final JLabel jLabel2 = new JLabel("中國民航大學 05B 張浩");
    public Explorer() 
    {
        //******初始化窗體,將其設置在正中
        Dimension dimension = getToolkit().getScreenSize();
        int i = (dimension.width - 640) / 2;
        int j = (dimension.height - 480) / 2;
        setBounds(i, j, 640, 480);
        //******
        setTitle("資源管理器");
        //******關閉窗口事件
        addWindowListener
        (
        new WindowAdapter() 
        {
            public void windowClosing(WindowEvent windowevent) 
            {
                System.exit(0);
            }
        }
        );
        //******
        //******初始化樹tree和list
        JScrollPane treeView = new JScrollPane(tree);
        treeView.setPreferredSize(new Dimension(200,200));
        
        JScrollPane listView = new JScrollPane(list);
        listView.setPreferredSize(new Dimension(300,600));

        split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT,treeView,listView);
        split.setLastDividerLocation(600);
        getContentPane().add(split);
        list.setBackground(Color.white);
        //******
        tree.addTreeExpansionListener(this);
        tree.addTreeSelectionListener(this);
        
        try 
        {
            UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
            SwingUtilities.updateComponentTreeUI(this);
        } 
        catch (Exception ex) {}
        
        //******設置地址欄的位置
        getContentPane().add(jLabel2,BorderLayout.SOUTH);
        getContentPane().add(jPanel1, BorderLayout.NORTH);
        jPanel1.add(jLabel1, BorderLayout.CENTER);
        //******
    }
//****************************實現借口TreeExpansionEvent的方法
    public void treeCollapsed(TreeExpansionEvent e) {}

    public void treeExpanded(TreeExpansionEvent e) 
    {
        if (tree.getLastSelectedPathComponent() == null) //返回當前選擇的第一個節點中的最后一個路徑組件
        {
            return;
        }
        if (tree.getLastSelectedPathComponent().toString().trim().equals("Local")) 
        {
            return;
        }
        TreePath path = e.getPath();//獲得節點的路徑
        //!!!!!!!!!!!
        FileNode node = (FileNode) path.getLastPathComponent();
        if (!node.isExtended()) 
        {
            DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
            node.Extend();
            model.nodeStructureChanged(node);
        }
        //!!!!!!!!!!!!!!!
    }
//*******************************************************************
  
//**********************************************實現接口TreeSelectionEvent的方法

    public void valueChanged(TreeSelectionEvent e)
    //該方法在改變選擇項時調用
    {
        try 
        {
            if (tree.getLastSelectedPathComponent() == null) 
            {
                return;
            }
            list.removeAll();
            if (tree.getLastSelectedPathComponent().toString().trim().equals("Local"))
                //點擊local返回各盤根目錄
            {
                File roots[] = File.listRoots();
                for (int i = 1; i < roots.length; i++) 
                {
                    String DiskName = roots[i].toString();
                    DiskName = DiskName.substring(0, DiskName.indexOf(":")+1);//D:\->D:
                    addButton(DiskName, "");//通過addButton將盤符添加到list中
                }
            } 
            else 
            {
                Object[] path = e.getPath().getPath();//返回第一個路徑元素的路徑
                String fileInfo = "";//記錄當前文件的路徑和名稱
                for (int i = 1; i < path.length; i++) 
                {
                    fileInfo += File.separator + path[i].toString();
                }
                File f = new File(fileInfo.substring(1));
                //System.out.print(fileInfo);//\C:\\WINDOWS
                jLabel1.setText(f.toString());
                String[] Tlist = f.list();
                Vector vFile = new Vector(), vDir = new Vector();
                for (int i = 0; i < Tlist.length; i++) 
                {
                    if ((new File(fileInfo + File.separator + Tlist[i])).isDirectory()) 
                    {
                        vDir.addElement(Tlist[i]);
                    } 
                    else 
                    {
                        vFile.addElement(Tlist[i]);
                    }
                }
                sortElements(vFile);
                sortElements(vDir);
                for (int i = 0; i < vDir.size(); i++) {
                    addButton((String) (vDir.elementAt(i)), fileInfo);
                }
                for (int i = 0; i < vFile.size(); i++) {
                    addButton((String) (vFile.elementAt(i)), fileInfo);
                }
            }
            list.doLayout();
            list.repaint();
        } 
        catch (Exception ee) {}
    }
//**********************************************************************************

//************************************************將list中的項按首字母排序
    public void sortElements(Vector v) 
    {
        for (int i = 0; i < v.size(); i++) 
        {
            int k = i;
            for (int j = i + 1; j < v.size(); j++) 
            {
                if (((String) (v.elementAt(j))).toLowerCase().compareTo(((String) (v.elementAt(k))).toLowerCase()) < 0)  
                {
                    k = j;
                }
            }
            if (k != i) 
            {
                swap(k, i, v);
            }
        }
    }
//***************************************************
    
//********************************交換函數
    private void swap(int loc1, int loc2, Vector v) 
    {
        Object tmp = v.elementAt(loc1);
        v.setElementAt(v.elementAt(loc2), loc1);
        v.setElementAt(tmp, loc2);
    }
//****************************************

 //*************list中項目以按鈕形式出現,每個文件為一個按鈕
    private void addButton(String fileName, String filePath) 
    {
        JButton btt = new JButton(fileName);
        btt.setBorder(null);
        btt.setHorizontalAlignment(SwingConstants.LEFT);
        btt.setBackground(Color.white);
        //******為按鈕添加圖標
        if ((new File(filePath + File.separator + fileName)).isDirectory()) 
        {
            btt.setIcon(UIManager.getIcon("Tree.closedIcon"));
        } 
        else 
        {
            btt.setIcon(UIManager.getIcon("Tree.leafIcon"));
        }
        //******
        list.add(btt);
        btt.addActionListener(this);
    }
//******************************************
    
 //********************************點擊tree中的節點和list中的按鈕出發事件
    public void actionPerformed(ActionEvent e) 
    {
        try
         {
            TreePath p = tree.getLeadSelectionPath();//點擊tree
            String fileName = ((JButton) (e.getSource())).getText();//點擊list
            Object[] path = p.getPath();
            String fileInfo = "";
            for (int i = 1; i < path.length; i++) 
            {
                fileInfo += File.separator + path[i].toString();//file.separator為分割符"\"
            }
            //System.out.print(ss);//\C:\\C:\\Borland
            fileInfo = fileInfo.substring(1);
            File f = new File(fileInfo + File.separator + fileName);
            jLabel1.setText(f.toString());
            if (f.isDirectory()) 
                //當選擇項為文件夾時
            {
                int index = tree.getRowForPath(p);
                tree.expandRow(index);
                while (!(tree.getLastSelectedPathComponent().toString().trim().equals(fileName))) 
                {
                    tree.setSelectionRow(index++);
                }
                tree.expandRow(index - 1);
            }
            else 
            {//為文件時,當遇如下后綴時，用記事本將其打開
                jLabel2.setText("文件大小:"+f.length()+"B");//顯示文件大小
                String postfix = fileName.toUpperCase();
                if (
                	postfix.indexOf(".TXT") != -1 ||
                        postfix.indexOf(".JAVA") != -1 ||
                        postfix.indexOf(".HTM") != -1 ||
                        postfix.indexOf(".LOG") != -1
                   ) 
                {
                    Runtime.getRuntime().exec("NotePad.exe " + fileInfo +File.separator + fileName);
                   // System.out.println(fileInfo +File.separator + fileName);
                    //System.out.println(fileInfo);
                     //System.out.println(File.separator);
                      //System.out.println(fileName);
                }
            }
        } 
        catch (Exception ee) {}
    }
//***************************************************************
    
//*********************************初始化樹型，獲得本地文件系統，將根目錄賦給樹
    private DefaultMutableTreeNode createTreeModel() 
    {
        DefaultMutableTreeNode rootNode = new DefaultMutableTreeNode("Local");//創建樹的根節點
        File[] rootPath = File.listRoots();//列出可用的文件系統根目錄c: d: e: f:
        for (int i = 1; i < rootPath.length; i++) 
        {
            FileNode Node = new FileNode(rootPath[i]);
            Node.Extend();
            rootNode.add(Node);
        }
        return rootNode;
    }
//****************************************************************************
    
    public static void main(String args[]) 
    {
        Explorer ex =new Explorer();
        ex.setVisible(true);
    }
}