Thread: JTree - file system viewer tree only with fixed file extensions

Hello,
I'm in the process of writing a school project and I have one problem i can't solve.
I have a tree that shows directories and file paths but I need to display only .mp3 and .wav files.
I have a class with a tree model:

import java.io.File;
import java.util.Iterator;
import java.util.Vector;
 
import javax.swing.JTextArea;
import javax.swing.event.TreeModelEvent;
import javax.swing.event.TreeModelListener;
import javax.swing.tree.TreeModel;
import javax.swing.tree.TreePath;
 
class FileSystemModel implements TreeModel {
	  private File root;
	  private JTextArea fileDetailsTextArea = new JTextArea();
	  private Vector listeners = new Vector();
 
	  public FileSystemModel(File rootDirectory) {
	    root = rootDirectory;
	  }
 
	  public Object getRoot() {
 
	    return root;
	  }
 
	  public Object getChild(Object parent, int index) {
	    File directory = (File) parent;
	    String[] children = directory.list();
 
	    return new TreeFile(directory, children[index]);
	  }
 
	  public int getChildCount(Object parent) {
	    File file = (File) parent;
	    if (file.isDirectory() ) {
	      String[] fileList = file.list();
	      if (fileList != null )
	        return file.list().length;
	    }
	    return 0;
	  }
 
	  public boolean isLeaf(Object node) {
	    File file = (File) node;
	    return file.isFile();
	  }
 
	  public int getIndexOfChild(Object parent, Object child) {
	    File directory = (File) parent;
	    File file = (File) child;
	    String[] children = directory.list();
	    for (int i = 0; i < children.length; i++) {
	      if (file.getName().equals(children[i])) {
	        return i;
	      }
	    }
	    return -1;
 
	  }
 
	  public void valueForPathChanged(TreePath path, Object value) {
	    File oldFile = (File) path.getLastPathComponent();
	    String fileParentPath = oldFile.getParent();
	    String newFileName = (String) value;
	    File targetFile = new File(fileParentPath, newFileName);
	    oldFile.renameTo(targetFile);
	    File parent = new File(fileParentPath);
	    int[] changedChildrenIndices = { getIndexOfChild(parent, targetFile) };
	    Object[] changedChildren = { targetFile };
	    fireTreeNodesChanged(path.getParentPath(), changedChildrenIndices, changedChildren);
 
	  }
 
	  private void fireTreeNodesChanged(TreePath parentPath, int[] indices, Object[] children) {
	    TreeModelEvent event = new TreeModelEvent(this, parentPath, indices, children);
	    Iterator iterator = listeners.iterator();
	    TreeModelListener listener = null;
	    while (iterator.hasNext()) {
	      listener = (TreeModelListener) iterator.next();
	      listener.treeNodesChanged(event);
	    }
	  }
 
	  public void addTreeModelListener(TreeModelListener listener) {
	    listeners.add(listener);
	  }
 
	  public void removeTreeModelListener(TreeModelListener listener) {
	    listeners.remove(listener);
	  }
 
	  private class TreeFile extends File {
	    public TreeFile(File parent, String child) {
	      super(parent, child);
	    }
 
	    public String toString() {
	      return getName();
	    }
	  }
 
	  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: " + (double)(file.length()/1024)/1024 + " MB" + "\n");
		    return buffer.toString();
		  }
	}

Can someone give me some advice how to do that?

Welcome to the forum! Thanks for taking the time to learn how to post code correctly. If you haven't already, please read this topic to learn other useful info for new members.

I haven't studied your code, but in general you should be able to filter the files to the ones desired using the file's extension. Review the File and String classes for the available options.

You are the best guys, thank u very much for fast answers.