filesystemmodel.java

java写的图片浏览器,类似acds

package org.net9.oops.jsee;
//import javax.swing.*;
import javax.swing.tree.*;
import java.io.*;

public class FileSystemModel extends AbstractTreeModel implements Serializable {
    String root;
    FileFilter filter;
    File[] children;
    File tempParent = null;

    public class MyFile extends File {
        public MyFile(String pathname) {
            super(pathname);
        }
        public File[] listFiles(FileFilter filter) {
            //return excludeNotReadyDrive(File.listRoots());
            String osName = System.getProperty("os.name",".");
            if (osName.startsWith("Windows"))
              return File.listRoots();
            else // only support Unix at the moment
              return super.listFiles(filter);
        }
    };

    public FileSystemModel() {
        root = "/"; //System.getProperty( "user.home" );
        filter = new FileFilter() {
            public boolean accept(File pathname) {
                return pathname.isDirectory();
            }
        };
    }

    public FileSystemModel( String startPath ) {
        root = startPath;
    }

    public Object getRoot() {
        return new MyFile( root );
    }

    public Object getChild( Object parent, int index ) {
      if (tempParent == null || !tempParent.equals((File)parent))
      {
          tempParent = (File)parent;
          try {
            children = tempParent.listFiles(filter);
          } catch (Exception ex) {return null;}
      }
      return children[index];
    }

    public int getChildCount( Object parent ) {
      if (tempParent == null || !tempParent.equals((File)parent))
      {
          tempParent = (File)parent;
          if ( tempParent.isDirectory() ) {
            //Modified by Neoya 2002-03-06
            try {
              children = tempParent.listFiles(filter);
              return children.length;
            } catch (Exception ex) {
              return 0;
            }
          } else {
            return 0;
          }
      } else {
          if ( tempParent.isDirectory() ) {
            if (children!=null)
              return children.length;
            else
              return 0;
          } else {
              return 0;
          }
      }
    }

    public boolean isLeaf( Object node ) { // Check if there is any file under node
    // Cast node to directory, list file in that directory to an array and compare array length
        //return ( ((File)node).listFiles(filter).length == 0 )? true:false;
    // To speed up - fast is better than look good
        return false;
    }

    public void valueForPathChanged( TreePath path, Object newValue ) {
    }

    public int getIndexOfChild( Object parent, Object child ) {
        if (tempParent == null || !tempParent.equals((File)parent))
        {
            tempParent = (File)parent;
            children = tempParent.listFiles(filter);
        }
        File fileSysEntity = (File)child;
        int result = -1;

        for ( int i = 0; i < children.length; ++i ) {
            if ( fileSysEntity.getName().equals( children[i] ) ) {
                result = i;
                break;
            }
        }
        return result;
    }
}