用java做一个本地文件查看器（资源浏览器）·····但是看不到C盘···求教
是用java写得文件浏览器····但是看不到C盘···其他盘都有···哪位高手帮忙改一改···
以下是代码：
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.tree.*;
import java.awt.*;
import java.awt.event.*;
import *;
import java.util.*;
public class scaner extends JFrame
implements ActionListener,TreeExpansionListener,TreeSelectionListener
{
//定义常量
JTree jtree = new JTree(createTreeModel());
JPanel JPsub=new JPanel(new GridLayout(100,3));
JPanel road=new JPanel(new BorderLayout());
JSplitPane JSP;
JLabel status=new JLabel(" ");
//构造函数
public scaner()
{
super("硬盘查看器");
//设置窗口大小
Dimension dimension = getToolkit().getScreenSize();
int i = 400;
int j = 100;
setBounds(i,j,640,480);
addWindowListener(
new WindowAdapter()
{
public void windowClosing(WindowEvent windowevent)
{
System.exit(0);
}
}
);
//水平分割窗口，左scrollPane内放tree，右放JPsub用于显示文件
JSP=new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, new JScrollPane(jtree),new JScrollPane(JPsub));
JSP.setLastDividerLocation(200);
getContentPane().add(JSP);
//背景色为白
JPsub.setBackground(Color.white);
//给树添加展开监听器
jtree.addTreeExpansionListener(this);
jtree.addTreeSelectionListener(this);
//设置树的外形 ,改变文件夹的图案
try {
UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
SwingUtilities.updateComponentTreeUI(this);
}
catch (Exception ex) {}
getContentPane().add(road,BorderLayout.NORTH);
road.add(status,BorderLayout.WEST);
}
//树展开
public void treeExpanded(TreeExpansionEvent e)
{
//getLastSelectedPathComponent()返回当前选择的第一个节点中的最后一个路径组件。
//首选节点的 TreePath 中的最后一个 Object，若未选择任何内容，则返回 null
if (jtree.getLastSelectedPathComponent()==null)
return;
if (jtree.getLastSelectedPathComponent().toString().trim().equals("Local"))
return;
TreePath tpath = e.getPath();
FileNode node = (FileNode)tpath.getLastPathComponent();
if( ! node.isExplored())
{
DefaultTreeModel model = (DefaultTreeModel)jtree.getModel();
node.Explore();
model.nodeStructureChanged(node);
}
}
//树折叠
public void treeCollapsed(TreeExpansionEvent e) {}
//值变化
public void valueChanged(TreeSelectionEvent e)
{
try{
String s="";
//如果该结点最后一个对象返回值为空，即为底层结点，返回，清空JPsub
if (jtree.getLastSelectedPathComponent()==null)
return;
JPsub.removeAll();
//如果是本地，则产生目录
if (jtree.getLastSelectedPathComponent().toString().trim().equals("Local"))
{
File roots[]=File.listRoots();//硬盘的名字
for(int i=1;i <roots.length;i++)
{
String DiskName=roots[i].toString();
DiskName=DiskName.substring(0,DiskName.indexOf(":")+1);
addButton(DiskName,"");
}
}
else
{
Object []path= e.getPath().getPath();
String st="";
for(int i=1;i <path.length;i++)
st+=File.separator+path[i].toString();
File f = new File(st.substring(1));
status.setText(f.toString());
String[] list= f.list();
//定义Vector变量 ，创建向量类Vector
Vector vFile=new Vector(),vDir=new Vector();
for(int i = 0; i < list.length; i++)
{
if ((new File(st+File.separator+list[i])).isDirectory())
vDir.addElement(list[i]);
else
vFile.addElement(list[i]);
}
//排序
sortElements(vFile);
sortElements(vDir);
for(int i=0;i <vDir.size();i++)
addButton((String)(vDir.elementAt(i)),st);
for(int i=0;i <vFile.size();i++)
addButton((String)(vFile.elementAt(i)),st);
}
JPsub.doLayout();
JPsub.repaint();
}
catch(Exception ee){}
}
//交换
private void swap(int loc1,int loc2,Vector v)
{
Object tmp=v.elementAt(loc1);
v.setElementAt(v.elementAt(loc2),loc1);
v.setElementAt(tmp,loc2);
}
//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);//进行交换
}
}
//添加右侧按钮 ，点击打开右侧文件夹
private void addButton(String fileName,String filePath)
{
JButton btt=new JButton(fileName);
btt.setBorder(null);
btt.setHorizontalAlignment(SwingConstants.LEFT);
btt.setBackground(Color.white);
if ((new File(filePath+File.separator+fileName)).isDirectory())
btt.setIcon(UIManager.getIcon("Tree.closedIcon"));
else
btt.setIcon(UIManager.getIcon("Tree.leafIcon"));
JPsub.add(btt);
btt.addActionListener(this);
}
//按钮动作 ，列出文件夹里面得文件，并显示相关文件类型
public void actionPerformed(ActionEvent e)
{
try
{
TreePath p=jtree.getLeadSelectionPath();
String text=((JButton)(e.getSource())).getText();
Object []path= p.getPath();
String sr="";
for(int i=1;i <path.length;i++)
sr+=File.separator+path[i].toString();
sr=sr.substring(1);
File f = new File(sr+File.separator+text);
status.setText(f.toString());
if(f.isDirectory())
{
int index=jtree.getRowForPath(p);
jtree.expandRow(index);
while (!(jtree.getLastSelectedPathComponent().toString().trim().equals(text)))
jtree.setSelectionRow(index++);
jtree.expandRow(index-1);
}
else
{
String postfix=text.toUpperCase();
if(postfix.indexOf(".TXT")!=-1||postfix.indexOf(".JAVA")!=-1||
postfix.indexOf(".HTM")!=-1||postfix.indexOf(".LOG")!=-1)
Runtime.getRuntime().exec("NotePad.exe "+sr+File.separator+text);
}
}
catch(Exception ee){}
}
//创建树
private DefaultMutableTreeNode createTreeModel()
{
DefaultMutableTreeNode rootNode=new DefaultMutableTreeNode("Local");
File[] rootPath = File.listRoots();
for(int i=1;i <rootPath.length;i++)
{
FileNode Node = new FileNode(rootPath[i]);
Node.Explore();
rootNode.add(Node);
}
return rootNode;
}
public static void main(String args[])
{
new scaner().setVisible(true);
}
class FileNode extends javax.swing.tree.DefaultMutableTreeNode
{
private boolean explored = false;
public FileNode(File file)
{
setUserObject(file);
}
@Override
public boolean getAllowsChildren()
{
return isDirectory();
}
@Override
public boolean isLeaf()
{
return !isDirectory();
}
public File getFile()
{
return (File)getUserObject();
}
public boolean isExplored()
{
return explored;
}
public boolean isDirectory()
{
return getFile().isDirectory();
}
@Override
public String toString()
{
File file = (File)getUserObject();
String filename = file.toString();
int index = filename.lastIndexOf(File.separator);
return (index != -1 && index != filename.length()-1) ? filename.substring(index+1) : filename;
}
public void Explore()
{
if(!isDirectory()) return;
if(!isExplored())
{
File file = getFile();
File[] children = file.listFiles();
for(int i=0; i < children.length; ++i)
{
File f=children[i];
if(f.isDirectory())add(new FileNode(children[i]));
}
explored = true;
}
}
}
}
