Get a certain node of a JTree

Hi to all!
I' m using JTree combined with DefaultMutableTreeNode and DefaultTreeModel.
My problem is that I have the path of a certain node and I just want to get a certain node of this path in order to edit (or better to update) its "userObject".
Maybe it's a silly question but I'm new to JTree and I feel a little lost with all these methods provided.
Thank you in advance.

For starters: excellent photography, and great lighting knowledge and skills. With great photography and lighting, you really don't need to do major alterations other than some minor improvements. i would say instead of looking for lightroom to make it better, instead improve the quality of your photos. lightroom is a tool, not a result to good photos.
with that said, reference these links:
http://thelightroomlab.com/2009/10/camera-raw-profiles-in-adobe-photoshop-lightroom/
http://layersmagazine.com/photographic-workflow-from-lightroom-to-photoshop.html
http://tv.adobe.com/watch/getting-started-with-adobe-photoshop-lightroom-4/lightroom-4-cre ate-stunning-images/
janelle

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How many nodes does this tree have?
import java.awt.EventQueue;
import javax.swing.*;
import javax.swing.event.TreeModelListener;
import javax.swing.tree.*;
public class BigTree {
    public static void main(String[] args) {
        EventQueue.invokeLater(new Runnable() {
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http://dotuseful.sourceforge.net/

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Hi everybody
I want to get TreePath for all the nodes in a JTree
Can anybody help me?

Hi,
i tried to used your code.
there is a problem, it is not taking the entire paths.
so if you have some children,it takes the paths only for the fathers.
so i correct it to the following way(it will take the entire paths):
public void getPathForAllNodes(TreePath path)
              Object node = path.getLastPathComponent();
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              return;
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I'm not exactly sure how to temporarily hide or filter nodes from a JTree. My scenario is described below.
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Here is my attempt to filter nodes. I get the following excpetion when I try to filter nodes:
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Thanks
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.DefaultMutableTreeNode;
public class MyTreeModel extends DefaultTreeModel
    * Constructor.
    * @param rootNode The root node.
   public MyTreeModel( DefaultMutableTreeNode rootNode )
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    * @param parent The parent node.
    * @param index The index this child node resides in.
    * @return The child node.
   public Object getChild( Object parent, int index )
      Object child = super.getChild( parent, index );
      if ( RadioBtn.hideNodes() )
         DefaultMutableTreeNode dmtn = ( DefaultMutableTreeNode ) child;
         MyNode eNode = ( MyNode ) dmtn.getUserObject();
         if ( !eNode.hasPermission() )
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    * @param child The child node.
    * @return The index of the child node.
    public int getIndexOfChild( Object parent, Object child )
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          if ( !eNode.hasPermission() )
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    * @return The number of children of the parent node.
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         for ( int x = 0; x < numChildren; x++ )
            DefaultMutableTreeNode childDmtn = ( DefaultMutableTreeNode ) dmtn.getChildAt( x );
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Here it is optimized, for anyone who may need the code down the road.
   public Object getChild( Object parent, int index )
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         DefaultMutableTreeNode dParent = ( DefaultMutableTreeNode ) parent;
         int count = 0;
         // Loop through children
         for ( int x = 0; x < dParent.getChildCount(); x++ )
            DefaultMutableTreeNode dChild = ( DefaultMutableTreeNode ) dParent.getChildAt( x );
            MyNode eNode = ( MyNode ) dChild.getUserObject();
            if ( eNode.hasPermission() )
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               if ( count == index )
                  child = dChild;
                  break;
               count++;
      return child;
   }

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It seems that in the TreeCellRender only kicks in when the tree is first displayed. How do I get it to re-render the tree when the TreeModel changes? It seems that the Listeners are only looking for external user interactions.
Any help would be greatly appreciated.
Thanks!

I think I was a bit too vague in my question. Let me try again...
I have changed an attribute in a node in a JTree. This attribute is changed after the tree was initially rendered, but while the program is still running. I want to tell the TreeCellRenderer to look again at this node since that attribute that was changed will effect how the node should be renderered. I tried using the nodeChanged() method, but it did not work (the colot of the node did not change). Any advise how I can do this?
Thanks!

Events of Nodes in a JTree

Okay, perhaps I am sidetracked today by all the sad craziness occuring in New York and DC, or perhaps I just don't have a grasp on JTrees yet...but...
I have implemented a TreeCellRender to create panels with buttons and other information to be the nodes of a JTree I created. Everything shows up beautifully, however, I want the buttons on this panel to depress and perfom actions (work like normal) when the user clicks/selects such a button in the tree structure. I can't figure out how to properly set up event handlers to get from the tree to the tree node to the "bean" I'm using as a node. If anyone has any helpful hints, I'd appreciate it!
Thanks in advance!

add actionlistener to the JTree, and then get the object by getLastPathComponent, and compare it if its the button and do the action.

Highlighting nodes in a JTree

Hi,
I'd like to know how I can produce the efect of highlighting nodes in a JTree when the mouse moves over the JTree.
Thanks

You say to get the mouseevent coordinates with a mouse
listener, but which component should be the caller of
the methos addMouseListener?
If I choose the jtree, I can't get the 'mouseevent
coordinates' each time the mouse moves over a node,
because the methods mouseEntered and mouseExited are
invoked just once (when the mouse enter inside the
jtree's area (mouseEntered), and when the mouse gets
out the jtree's area(mouseExited)), so I can't change
the boolean field to true for nodes which have the
mouse over.just use mouseMoved of the MouseMotionListener.
however, i have my doubts that you will have a lot of fun with the suggested method (correct though it is).
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hi,
i saw that tutorial.from that book i dont get the particular node cell renderer.i got a cell renderer for tree only.i attached my code in this mail.pls see and help me if u will do
mport pack.Prop;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Container;
import java.awt.Font;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.Properties;
import java.util.Set;
import java.util.StringTokenizer;
import java.util.Vector;
import javax.swing.Icon;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.UIManager;
import javax.swing.text.Position;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.MutableTreeNode;
import javax.swing.tree.TreeCellRenderer;
import javax.swing.tree.TreePath;
public class ReadProperty3 extends JFrame{
String str,key;
static JTree tree;
static Vector v;
StringTokenizer st;
static DefaultMutableTreeNode root;
DefaultMutableTreeNode t;
public Object[] o;
public static void main(String[] args) throws IOException {
ReadProperty3 r = new ReadProperty3();
Prop p=new Prop();
JFrame f=new JFrame();
p.show();
Object[] o=v.toArray();
int startRow = 0;
String prefix =p.s;
TreePath path = tree.getNextMatch(prefix, startRow, Position.Bias.Forward);
//if(prefix.equals(root.getChildAt(0).toString()))
if(prefix.equals("2000"))
     System.out.println("Node 2000 found");
     else if(prefix.equals("3000"))
          System.out.println("Node 3000 found");
     else if(prefix.equals("4000"))
          System.out.println("Node 4000 found");
     else
          System.out.println("Node not found");
     for(int i=0;i<v.size();i++)
          //((DefaultTreeModel)tree.getModel()).reload();
          DefaultTreeCellRenderer ren=(DefaultTreeCellRenderer)tree.getCellRenderer();
          Icon openIcon = new ImageIcon("C:/apache-tomcat-5.5.12/webapps/jsp-examples/images/execute.gif");
          Icon closedIcon = new ImageIcon("C:/apache-tomcat-5.5.12/webapps/jsp-examples/images/execute.gif");
          Icon leafIcon = new ImageIcon("C:/apache-tomcat-5.5.12/webapps/jsp-examples/images/read.gif");
          if(o[0].equals(p.s))
               ren.setBackgroundSelectionColor(Color.MAGENTA);
               ren.setBackgroundNonSelectionColor(Color.YELLOW);
               //ren.setTextSelectionColor(Color.YELLOW);
               //ren.setTextNonSelectionColor(Color.BLUE);
               ren.setClosedIcon(closedIcon);
               ren.setFont(new Font("Impact",Font.ITALIC,14));
          else if(o[1].equals(p.s))
               ren.setLeafIcon(leafIcon);
               ren.setFont(new Font("Impact",Font.ITALIC,10));
               UIManager.put("Tree.leafIcon", leafIcon);
          else if(o[2].equals(p.s))
               ren.setOpenIcon(openIcon);
               ren.setFont(new Font("Dialog",Font.BOLD,9));
public ReadProperty3(){
     super("JTree With Properties");
     try{
int c = 0;
while(c == 0){
c = 1;
BufferedReader bf = new BufferedReader(new InputStreamReader(System.in));
System.out.print("Enter file name which has properties extension :");
str = bf.readLine();
File f = new File(str + ".properties");
if(f.exists()){
Properties pro = new Properties();
FileInputStream in = new FileInputStream(f);
pro.load(in);
System.out.println("Key: " + pro.keySet());
System.out.print("Enter Key : ");
key = bf.readLine();
String p = pro.getProperty(key);
st = new StringTokenizer(p,"=,");
root=new DefaultMutableTreeNode(key);
v=new Vector();
while(st.hasMoreTokens())
     String val=st.nextToken();
     v.add(val);
     o=v.toArray();
     System.out.println(val);
     t=new DefaultMutableTreeNode(val);
     root.add(t);
     tree=new JTree(root);
     tree.setEditable(true);
     JScrollPane jp=new JScrollPane(tree);
     // tree.setCellRenderer(new CellRenderer());
     Container content=getContentPane();
     content.add(jp,BorderLayout.CENTER);
setSize(250,275);
setVisible(true);
addWindowListener(new ExitListener());
else{
c = 0;
System.out.println("File not found!");
catch(IOException e){
System.out.println(e.getMessage());
}

Changing Certain Node Icons

I can't seem to figure out how to change certain node icons in a JTree due to a 3 letter string. For example 2 nodes one saying "Intro" the other say "Edit - SEC" - the one with SEC has a different icon to "Intro"
MyRenderer class, here the code which is used to check the string of the node......
if(leaf && isSecuredFile(value)) {
setLeafIcon(leafSecuredIcon);
setToolTipText("This file is Secured Access Only");
else {
setToolTipText(null);
return this;
protected boolean isSecuredFile(Object value) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;
NodeRecord nodeInfo = (NodeRecord)(node.getUserObject());
String nodeTitle = nodeInfo.NodeRecord;
if(nodeTitle.indexOf("SEC") >= 0) {
return true;
return false;
}// MyRenderer class
I tried the above piece of code, and it compiles with no errors but when I try to run the applet it comes up not initialised with the following....
java.lang.NoClassDefFoundError: MyRenderer
at firstPanel.<init>(firstPanel.java:99)
at JNavigator.jInit(JNavigator.java:55)
at JNavigator.init(JNavigator.java:40)
at sun.applet.AppletPanel.run(AppletPanel.java:344)
at java.lang.Thread.run(Thread.java:484)
However if I take out this code it works fine but I need to be able to assign different icons depending on the node title string. Therefore I need help.

here's the whole class, if thats any help...
public class MyRenderer extends DefaultTreeCellRenderer {
ImageIcon leafIcon;
ImageIcon leafSecuredIcon;
public MyRenderer() {
leafIcon = new ImageIcon("Leaf.gif");
leafSecuredIcon = new ImageIcon("LeafSecured.gif");
public Component getTreeCellRendererComponent(JTree tree, Object val, boolean sel, boolean expand, boolean leaf, int row, boolean hasFocus) {
super.getTreeCellRendererComponent(tree, val, sel, expand, leaf, row, hasFocus);
// sets Icons
setLeafIcon(leafIcon);
setClosedIcon(new ImageIcon("Folder95C.gif"));
setOpenIcon(new ImageIcon("Folder95O.gif"));
// set Expansion icons to + -
ComponentUI treeUI = tree.getUI();
if(treeUI instanceof BasicTreeUI) {
((BasicTreeUI)treeUI).setExpandedIcon(new ImageIcon("minus.gif"));
((BasicTreeUI)treeUI).setCollapsedIcon(new ImageIcon("plus.gif"));
// decides who icon to use
if(leaf && isSecuredFile(value)) {
setLeafIcon(leafSecuredIcon);
setToolTipText("This file is Secured Access Only");
else {
setToolTipText(null);
return this;
protected boolean isSecuredFile(Object value) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode)value;
NodeRecord nodeInfo = (NodeRecord)(node.getUserObject());
String nodeTitle = nodeInfo.NodeRecord;
if(nodeTitle.indexOf("DOM") >= 0) {
return true;
return false;
}

Get a certain node of a JTree

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