DisclosureIcon on empty branches in Tree

Hello,
I'm trying to display XML data in a tree. Because of the way
the XML looks, I needed to write a custom data descriptor (I'll
explain the XML structure at the end of the post) with custom
hasChildren and
isBranch methods.
Now I've got the problem that everything works fine, but
empty branches will still have the disclosure icon displayed. So
apparently the data passed to the default itemRenderer is not
"delivered" by the data descriptor - or the data descriptor
delivers something to the renderer in a way that's incorrect.
Either way, the TreeItemRenderer will show
_listData.hasChildren to be true, while the data
descriptor's
hasChildren will show it to be false.
Assuming the data descriptor is okay, is there any way to
access the original XML from within a custom treeItemRenderer so
that I can "check for children myself"?
(on a second issue, I would also need to display a specific
image with each tree leaf, depending on how an XML attribute of the
leaf is set - similar to the Windows Explorer showing different
icons for different file types - again, this would only work if I
had access to the XML structure from within the renderer)
Any help is much appreciated,
cheers,
Fabian
XML Structure:
Branches and Leaves are both received as <folder> tags.
Both leaves and branches can have <property> tags, which are
not to be displayed. The only difference between a branch and a
leaf is that the leaves have a <property
name='url'>url</property> tag, while the branches do not
have property tags with a "name" attribute set to "url".
Example:
<folder id="thisIsTheRootFolder>
<property name="someProp">someValue</property>
/not to be displayed at all
<folder id="firstSubfolder">
/this should be an empty subfolder
<property
name="someOtherProp">someOtherValue</property>
</folder>
<folder id="secondSubfolder">
<folder id="thisIsALeaf">
<property name="url">
http://www.adobe.com</property>
</folder>
</folder>
</folder>

Nodes of the tree are represented by the TreeDataProvider
control. For each node in the tree, the TreeDataProvider control
can define the following properties:
data - The data to associate with a node, if any.
label - The text to be displayed in the Tree for a node.
isBranch - If true, the node is a branch: if false, it is not
a branch. If not specified, the Tree control determines if the node
is a branch based on whether it contains any child nodes.

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Can't remove a node from a tree

I am using the custom tree dataDescriptor provided in Flex live
doc. It works for creating the tree and add notes, however when I
try to remove a node from the tree it cant work. Does anyone have
any idea?
This is the code for MyCustomeTreeDataDescriptor.as
package
import mx.collections.ArrayCollection;
import mx.collections.CursorBookmark;
import mx.collections.ICollectionView;
import mx.collections.IViewCursor;
import mx.events.CollectionEvent;
import mx.events.CollectionEventKind;
import mx.controls.treeClasses.*;
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ITreeDataDescriptor
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// with a children field.
// If the field contains an ArrayCollection, it returns the
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// Otherwise, it wraps the field in an ArrayCollection.
public function getChildren(node:Object,
model:Object=null):ICollectionView
try
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}else{
return new ArrayCollection(node.children);
catch (e:Error) {
trace("[Descriptor] exception checking for getChildren");
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// Object with a children field.
// It does not support empty branches, but does support null
children
// fields.
public function isBranch(node:Object,
model:Object=null):Boolean {
try {
if (node is Object) {
if (node.children != null) {
return true;
catch (e:Error) {
trace("[Descriptor] exception checking for isBranch");
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// The hasChildren method Returns true if the node actually
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public function hasChildren(node:Object,
model:Object=null):Boolean {
if (node == null)
return false;
var children:ICollectionView = getChildren(node, model);
try {
if (children.length > 0)
return true;
catch (e:Error) {
return false;
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public function getData(node:Object,
model:Object=null):Object {
try {
return node;
catch (e:Error) {
return null;
// The addChildAt method does the following:
// If the parent parameter is null or undefined, inserts
// the child parameter as the first child of the model
parameter.
// If the parent parameter is an Object and has a children
field,
// adds the child parameter to it at the index parameter
location.
// It does not add a child to a terminal node if it does not
have
// a children field.
public function addChildAt(parent:Object, child:Object,
index:int,
model:Object=null):Boolean {
var event:CollectionEvent = new
CollectionEvent(CollectionEvent.COLLECTION_CHANGE);
event.kind = CollectionEventKind.ADD;
event.items = [child];
event.location = index;
if (!parent) {
var iterator:IViewCursor = model.createCursor();
iterator.seek(CursorBookmark.FIRST, index);
iterator.insert(child);
else if (parent is Object) {
if (parent.children != null) {
if(parent.children is ArrayCollection) {
parent.children.addItemAt(child, index);
if (model){
model.dispatchEvent(event);
model.itemUpdated(parent);
return true;
else {
parent.children.splice(index, 0, child);
if (model)
model.dispatchEvent(event);
return true;
return false;
// The removeChildAt method does the following:
// If the parent parameter is null or undefined, removes
// the child at the specified index in the model.
// If the parent parameter is an Object and has a children
field,
// removes the child at the index parameter location in the
parent.
public function removeChildAt(parent:Object, child:Object,
index:int, model:Object=null):Boolean
var event:CollectionEvent = new
CollectionEvent(CollectionEvent.COLLECTION_CHANGE);
event.kind = CollectionEventKind.REMOVE;
event.items = [child];
event.location = index;
//handle top level where there is no parent
if (!parent)
var iterator:IViewCursor = model.createCursor();
iterator.seek(CursorBookmark.FIRST, index);
iterator.remove();
if (model)
model.dispatchEvent(event);
return true;
else if (parent is Object)
if (parent.children != undefined)
parent.children.splice(index, 1);
if (model)
model.dispatchEvent(event);
return true;
return false;
This is my tree definition:
<mx:Tree width="143" top="0" bottom="0" left="0"
height="100%"
id="publicCaseTree"
dataDescriptor="{new MyCustomTreeDataDescriptor()}"
dataProvider="{ac}"
defaultLeafIcon="@Embed('assets/caseIcon.png')"
change="publicTreeChanged(event)"
dragEnabled="true"
dragMoveEnabled="false"/>
This is how I remove the selected node from the tree. When
Delete button is clicked, the doDeleteCase function is
exectuted.
public function publicTreeChanged(event:Event):void {
selectedNode =
publicCaseTree.dataDescriptor.getData(Tree(event.target).selectedItem,
ac);
public function doDeleteCase(event:Event):void{
publicCaseTree.dataDescriptor.removeChildAt(publicCaseTree.firstVisibleItem,
selectedNode, 0, ac);
Any help would be appreciated.Thanks.

Finally I removed nodes from tree, but not sure I did in the
right way. Anybody encounter the same problem, please
discuss.

Cannot resolve attribute 'treeDataDescriptor' for component type mx.controls.Tree.

Hi,
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treeEx1.mxml
<?xml version="1.0" encoding="iso-8859-1"?>
<mx:Application xmlns:mx="
http://www.adobe.com/2006/mxml"
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<mx:Script>
<![CDATA[
import mx.collections.*;
import mx.controls.treeClasses.*;
import customComp.MyCustomTreeDataDescriptor;
//Variables used to construct the ArrayCollection data
provider
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public var nestArray1:Object = [
{label:"item1", children: [
{label:"item1 child", children: [
{label:"item 1 child child", data:"child data"}
//Second top-level node and its children.
public var nestArray2:Object = [
{label:"item2", children: [
{label:"item2 child", children: [
{label:"item 2 child child", data:"child data"}
//Second top-level node and its children.
public var nestArray3:Object = [
{label:"item3", children: [
{label:"item3 child", children: [
{label:"item 3 child child", data:"child data"}
//Variable for the tree array.
public var treeArray:Object
//Variables for the three Array collections that correspond
to the
//top-level nodes.
public var col1:ArrayCollection;
public var col2:ArrayCollection;
public var col3:ArrayCollection;
//Variable for the ArrayCollection used as the Tree data
provider.
[Bindable]
public var ac:ArrayCollection;
//build the ac ArrayCollection from its parts.
public function initCollections():void{
// Wrap each top-level node in an ArrayCollection.
col1 = new ArrayCollection(nestArray1);
col2 = new ArrayCollection(nestArray2);
col3 = new ArrayCollection(nestArray3);
// Put the three top-level node ArrayCollections in the
treeArray.
treeArray = [
{label:"first thing", children: col1},
{label:"second thing", children: col2},
{label:"third thing", children: col3},
//Wrap the treeArray in an ArrayCollection.
ac = new ArrayCollection(treeArray);
// Adds a child node as the first child of the selected
node,
// if any. The default selectedNode is null, which causes
the
// data descriptor addChild method to add it as the first
child
// of the ac ArrayCollection.
public function clickAddChildren():void {
var newChild:Object = new Object();
newChild.label = "New Child";
newChild.children = new ArrayCollection();
tree.treeDataDescriptor.addChildAt(tree.selectedNode,
newChild, 0, ac);
]]>
</mx:Script>
<mx:Tree width="200" id="tree" dataProvider="{ac}"
treeDataDescriptor="{new MyCustomTreeDataDescriptor()}"/>
<mx:Button label="add children"
click="clickAddChildren()"/>
</mx:Application>
and
and MyCustomTreeDataDescriptor.as :
package customComp.MyCustomTreeDataDescriptor
import mx.collections.ICollectionView;
import mx.collections.IViewCursor;
import mx.events.TreeModelChangedEvent;
import mx.events.TreeModelChangedEventDetail;
import mx.controls.treeClasses.*;
public class MyCustomTreeDataDescriptor implements
ITreeDataDescriptor
// The getChildren method requires the node to be an Object
// with a children field.
// If the field contains an ArrayCollection, it returns the
field
// Otherwise, it wraps the field in an ArrayCollection.
public function getChildren(node:Object,
model:Object=null):ICollectionView
try
if (node is Object)
if(node.children is ArrayCollection){
return node.children;
}else{
return new ArrayCollection(node.children);
catch (e:Error)
trace("[Descriptor] exception checking for getChildren");
return null;
// The isBranch method simply returns true if the node is an
// Object with a children field.
// It does not support empty branches, but does support null
children
// fields.
public function isBranch(node:Object,
model:Object=null):Boolean
try
if (node is Object)
if (node.children != null)
return true;
catch (e:Error)
trace("[Descriptor] exception checking for isBranch");
return false;
// The getData method simply returns the node as an Object.
public function getData(node:Object,
model:Object=null):Object
try
return Object(node);
catch (e:Error)
return null;
// The addChildAt method does the following:
// If the node parameter is null or undefined, inserts
// the child parameter as the first child of the model
parameter.
// If the node parameter is an Object and has a children
field,
// adds the child parameter to it at the index parameter
location.
// It does not add a child to a terminal node if it does not
have
// a children field.
public function addChildAt(node:Object, child:Object,
index:int, model:Object=null):Boolean
var event:TreeModelChangedEvent = new
TreeModelChangedEvent("modelChanged", false, false,
TreeModelChangedEventDetail.ADD_NODE, child, node, index);
if (!node)
var iterator:IViewCursor = model.createCursor();
iterator.seek(CursorBookmark.FIRST, index);
iterator.insert(child);
else if (node is Object)
if (node.children != null)
if(node.children is ArrayCollection) {
node.children.addItemAt(child, index);
if (model){
model.dispatchEvent(event);
model.itemUpdated(node);
return true;
else {
node.children.splice(index, 0, child);
if (model)
model.dispatchEvent(event);
return true;
return false;
I have read the docs and looked through some example on this
form but I still can't figure it out .
Thanks
The code above is from:
http://127.0.0.1:56812/help/topic/com.adobe.flexbuilder.help/html/Part2_DevApps.html
Using hierarchical data providers

I hav echnaged it and now I get :
A file found in an source-path must have the same package
structure 'customComp', as the definition's package,
'customComp.MyCustomTreeDataDescriptor'.
I tried different variations but nothing seems to work. I
have the following folder structure:
\Lessons
\customComp
.MyCustomTreeDataDescriptor.as
treeEx1.mxml
Thanks

Listing File Hierarchy in console using a Tree structure

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startingdir
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import java.util.ListIterator;
import java.util.NoSuchElementException;
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        newChild.parent = node;
        node.children.addLast(newChild);
        return newChild;
    public E element (Node node) {
         return node.getElement();
    //////////// Iterators ////////////
    public Iterator childrenIterator (Node node) {
        return node.children.iterator();
    public Iterator nodesPreOrder () {
    // Return an iterator that visits all nodes of this tree, with a pre-order
    // traversal.
        return new Tree.PreOrderIterator();
    //////////// Inner classes ////////////
    public class Node {
        // Each Tree.Node object is a node of an
        // unordered tree, and contains a single element.
        // This tree node consists of an element (element),
        // a link to its parent
        // and a LinkedList of its children
        private E element;
        private Node parent;
        private LinkedList<Node> children;
        private Node (E elem) {
            // Construct a tree node, containing element elem, that has no
            // children and no parent.
            this.element = elem;
            this.parent = null;
            children = new LinkedList<Node>();
        public E getElement () {
        // Return the element contained in this node.
            return this.element;
        public String toString () {
        // Convert this tree node and all its children to a string.
            String children = "";
            // write code here to add all children
            return element.toString() + children;
        public void setElement (E elem) {
        // Change the element contained in this node to be elem.
            this.element = elem;
    public class PreOrderIterator implements Iterator {
        private Deque<Node> track; //Java recommends using Deque rather
        // than Stack. This is used to store sequence of nomempty subtrees still
        //to be visited
        private PreOrderIterator () {
            track = new LinkedList();
            if (root != null)
                track.addFirst(root);
        public boolean hasNext () {
            return (! track.isEmpty());
        public E next () {
            Node place = track.removeFirst();
            //stack the children in reverse order
            if (!place.children.isEmpty()) {
                int size = place.children.size(); //number of children
                ListIterator<Node> lIter =
                        place.children.listIterator(size); //start iterator at last child
                while (lIter.hasPrevious()) {
                    Node element = lIter.previous();
                    track.addFirst(element);
            return place.element;
        public void remove () {
            throw new UnsupportedOperationException();
    FileHierarchy.java
import java.io.File;
import java.util.Iterator;
public class FileHierarchy {
    // Each FileHierarchy object describes a hierarchical collection of
    // documents and folders, in which a folder may contain any number of
    // documents and other folders. Within a given folder, all documents and
    // folders have different names.
    // This file hierarchy is represented by a tree, fileTree, whose elements
    // are Descriptor objects.
    private Tree fileTree;
    //////////// Constructor ////////////
    public FileHierarchy (String startingDir, int level) {
        // Construct a file hierarchy with level levels, starting at
        // startingDir
        // Can initially ignore level and construct as many levels as exist
        fileTree = new Tree();
        Descriptor descr = new Descriptor(startingDir, true);
        fileTree.makeRoot(descr);
        int currentLevel = 0;
        int maxLevel = level;
        addSubDirs(fileTree.root(), currentLevel, maxLevel);
    //////////// File hierarchy operations ////////////
    private void addSubDirs(Tree.Node currentNode, int currentLevel,
            int maxLevel) {
    // get name of directory in currentNode
    // then find its subdirectories (can add files later)
    // for each subdirectory:
    //    add it to children of currentNode - call addChild method of Tree
    //    call this method recursively on each child node representing a subdir
    // can initially ignore currentLevel and maxLevel
        Descriptor descr = (Descriptor) currentNode.getElement();
        File f = new File(descr.name);
        File[] list = f.listFiles();
        for (int i = 0; i < list.length; ++i) {
            if (list.isDirectory()) {
File[] listx = null;
fileTree.addChild(currentNode, i);
if (list[i].list().length != 0) {
listx = list[1].listFiles();
addSubDirs(currentNode,i,1);
} else if (list[i].isFile()) {
fileTree.addChild(currentNode, i);
// The following code is sample code to illustrate how File class is
// used to get a list of subdirectories from a starting directory
// list now contains subdirs and files
// contained in dir descr.name
////////// Inner class for document/folder descriptors. //////////
private static class Descriptor {
// Each Descriptor object describes a document or folder.
private String name;
private boolean isFolder;
private Descriptor (String name, boolean isFolder) {
this.name = name;
this.isFolder = isFolder;
FileHierarchyTest.javapublic class FileHierarchyTest {
private static Tree fileTree;
public static void main(String[] args) {
FileHierarchy test = new FileHierarchy ("//test", 1);
System.out.println(test.toString());

Denis,
Do you have [red hair|http://www.dennisthemenace.com/]? ;-)
My advise with the tree structure is pretty short and sweet... make each node remember
1. it's parent
2. it's children
That's how the file system (inode) actually works.
<quote>
The exact reasoning for designating these as "i" nodes is unsure. When asked, Unix pioneer Dennis Ritchie replied:[citation needed]
In truth, I don't know either. It was just a term that we started to use. "Index" is my best guess, because of the
slightly unusual file system structure that stored the access information of files as a flat array on the disk, with all
the hierarchical directory information living aside from this. Thus the i-number is an index in this array, the
i-node is the selected element of the array. (The "i-" notation was used in the 1st edition manual; its hyphen
became gradually dropped).</quote>

A Binary Tree Implementation in ABAP

Hi,
Can any one explaine me how to create a binary tree of random numbers with dynamic objects.
Thanks,
Manjula.

Hi manjula,
This sample code uses dynamic objects to create a binary tree of random numbers as per your requirement ...pls go through It.
It stores numbers on the left node or right node depending on the value comparison with the current value. There are two recursive subrotines used for the building of the tree and printing through the tree.
For comparison purpose, the same random numbers are stored and sorted in an internal table and printed.
*& Report YBINTREE - Build/Print Binary Tree of numbers *
report ybintree .
types: begin of stree,
value type i,
left type ref to data,
right type ref to data,
end of stree.
data: tree type stree.
data: int type i.
data: begin of rnd occurs 0,
num type i,
end of rnd.
start-of-selection.
do 100 times.
generate random number between 0 and 100
call function 'RANDOM_I4'
exporting
rnd_min = 0
rnd_max = 100
importing
rnd_value = int.
store numbers
rnd-num = int.
append rnd.
build binary tree of random numbers
perform add_value using tree int.
enddo.
stored numbers are sorted for comparison
sort rnd by num.
print sorted random numbers
write: / 'Sorted Numbers'.
write: / '=============='.
skip.
loop at rnd.
write: rnd-num.
endloop.
skip.
print binary tree. This should give the same result
as the one listed from the internal table
write: / 'Binary Tree List'.
write: / '================'.
skip.
perform print_value using tree.
skip.
*& Form add_value
text - Build tree with value provided
-->TREE text
-->VAL text
form add_value using tree type stree val type i.
field-symbols: <ltree> type any.
data: work type stree.
if tree is initial. "When node has no values
tree-value = val. " assign value
clear: tree-left, tree-right.
create data tree-left type stree. "Create an empty node for left
create data tree-right type stree. "create an empty node for right
else.
if val le tree-value. "if number is less than or equal
assign tree-left->* to <ltree>. "assign the left node to fs
call add_value recursively with left node
perform add_value using <ltree> val.
else. "if number is greater
assign tree-right->* to <ltree>. "assign the right node to fs
call add_value recursively with right node
perform add_value using <ltree> val.
endif.
endif.
endform. "add_value
*& Form print_value
text - traverse tree from left-mid-right order
automatically this will be sorted list
-->TREE text
form print_value using tree type stree.
field-symbols: <ltree> type any.
if tree is initial. "node is empty
else. "non-empty node
assign tree-left->* to <ltree>. "left node
perform print_value using <ltree>. "print left
write: tree-value. "print the current value
assign tree-right->* to <ltree>. "right node
perform print_value using <ltree>. "print right
endif.
endform. "print_value
pls reward if helps,
regards.

ADF Query Panel with Tree Table

I am using JDev 11g to create ADF Query Panel withTree Table. Basically it's working on data part.
But on presentation part it looks awkward. The tree table's master row and child row share first row for column name
ColumnMaster1 ColumnMaster2 ColumnMaster3 ColumnChild1 ColumnChild2 ColumnChild3
So when tree closed, the master side filled. Child side empty. When tree opened, master side empty and child side filled.
Are there any way, to make it inline looking with it's own column name for child?
Thanks in advance.
Edited by: kxc on Oct 30, 2009 9:19 AM

Hi,
the bug got closed already as not a bug. Instead this is filed as a documentation bug now, saying that tree tables don't support wrapped columns. So the bottom line is that three tables can only have a single leading column. If you need to show multiple information in there then I guess you will concatenate this
Frank

Binary search tree errors

MORE A CRY FOR HELP THEN A QUESTION-THANKS!
I'm having some diffucilites debugging errors produced by my binary search tree class. Spent alot of time trying correct them but just doesn't seem to be working for me :|!. I'm working with two main classes BinaryNode and BinarySearchTree.
class BinaryNode<AnyType> extends BinarySearchTree
    // Constructor
    BinaryNode(AnyType theElement)
        element = theElement;
        left = right = null;
      // Data; accessible by other package routines
    AnyType             element; // The data in the node
    BinaryNode<AnyType> left;     // Left child
    BinaryNode<AnyType> right;    // Right child
public class BinarySearchTree<AnyType extends Comparable<? super AnyType>>
      /** The tree root. */
    protected BinaryNode<AnyType> root;
    private int[] unsorted = new int[] {3,6,7,2,1};
     * Construct the tree.
    public BinarySearchTree()
     root = null;
     * Insert into the tree.
     * @param x the item to insert.
     * @throws DuplicateItemException if x is already present.
    public void insert(AnyType x)
        root = insert(x, root);
     * Remove from the tree..
     * @param x the item to remove.
     * @throws ItemNotFoundException if x is not found.
    public void remove(AnyType x)
        root = remove(x, root);
     * Remove minimum item from the tree.
     * @throws ItemNotFoundException if tree is empty.
    public void removeMin()
        root = removeMin(root);
     * Find the smallest item in the tree.
     * @return smallest item or null if empty.
    public BinaryNode<AnyType> findMin()
     //uses a helpler method that iterates over the left hand of the binary tree
        return(findMin(root));
     * Find the largest item in the tree.
     * @return the largest item or null if empty.
    public BinaryNode<AnyType> findMax()
        return (findMax(root));
     * Find an item in the tree.
     * @param x the item to search for.
     * @return the matching item or null if not found.
    public AnyType find(AnyType x)
        return elementAt(find(x,root));
     * Make the tree logically empty.
    public void makeEmpty()
        root = null;
     * Test if the tree is logically empty.
     * @return true if empty, false otherwise.
    public boolean isEmpty()
        return root == null;
     * Internal method to get element field.
     * @param t the node.
     * @return the element field or null if t is null.
    public AnyType elementAt(BinaryNode<AnyType> t)
        return t == null ? null : t.element;
     * Internal method to insert into a subtree.
     * @param x the item to insert.
     * @param t the node that roots the tree.
     * @return the new root.
     * @throws DuplicateItemException if x is already present.
    protected BinaryNode<AnyType> insert(AnyType x, BinaryNode<AnyType> t)
        if(t == null) {
            t = new BinaryNode<AnyType>(x);
        else if(x.compareTo(t.element) < 0) {
            t.left = insert(x, t.left);
        else if(x.compareTo(t.element) > 0 ) {
            t.right = insert(x, t.right);
        else {
            throw new DuplicateItemException(x.toString()); // Duplicate
        return t;
     * Internal method to remove from a subtree.
     * @param x the item to remove.
     * @param t the node that roots the tree.
     * @return the new root.
     * @throws ItemNotFoundException if x is not found.
    protected BinaryNode<AnyType> remove(AnyType x, BinaryNode<AnyType> t)
        if(t == null) {
            throw new ItemNotFoundException(x.toString());
        if(x.compareTo(t.element) < 0) {
            t.left = remove(x,t.left);
        else if(x.compareTo(t.element) > 0) {
            t.right = remove(x, t.right);
        else if(t.left != null && t.right != null) // Two children
            t.element = findMin(t.right).element;
            t.right = removeMin(t.right);
        else {
            t = (t.left != null) ? t.left : t.right;
        return t;
     * Internal method to remove minimum item from a subtree.
     * @param t the node that roots the tree.
     * @return the new root.
     * @throws ItemNotFoundException if t is empty.
    protected BinaryNode<AnyType> removeMin(BinaryNode<AnyType> t)
        if(t == null) {
            throw new ItemNotFoundException();
        else if(t.left != null) {
            t.left = removeMin(t.left);
            return t;
        else {
            return t.right;
    * Given a non-empty binary search tree,
    * return the minimum data value found in that tree.
    * Note that the entire tree does not need to be searched.
    * @param t the node that roots the tree.
    * @return node containing the smallest item.
    protected BinaryNode<AnyType> findMin(BinaryNode<AnyType> t)
        if(t != null) {
            while(t.left != null) {
                t = t.left;
        return t; //the smallest value
     * Internal method to find the largest item in a subtree.
     * @param t the node that roots the tree.
     * @return node containing the largest item.
    protected BinaryNode<AnyType> findMax(BinaryNode<AnyType> t)
        if(t != null) {
            while(t.right != null) {
                t = t.right;
        return t; //the largest value
     * Internal method to find an item in a subtree.
     * @param x is item to search for.
     * @param t the node that roots the tree.
     * @return node containing the matched item.
    private BinaryNode<AnyType> find(AnyType x, BinaryNode<AnyType> t)
        while(t != null) {
            if(x.compareTo(t.element) < 0) {
                t = t.left;
            else if(x.compareTo(t.element) > 0) {
                t = t.right;
            else {
                return t;    // Match
        return null;         // Not found
    public void betweenTraverse() {
     betweenTraverse(root);
    * Given two integers,
    * print all the values in the tree which are between these two numbers
    * in ascending order.
    * @param t is BinaryTree to search through
    * @param a is min integer to start print from
    * @param b is max integer to keep integer print between
    private void betweenTraverse(BinaryNode<AnyType> t)
     //enter samllest vaule
     int a = System.in.read();
     //enter largetest vaule
     int b = System.in.read();
     if (t != null) {
         inorderTraverse(t.left);
         if(t.elementAt(t) >a && t.elementAt(t) < b) { //LINE 274 with error
          System.out.println(t.elementAt(t));
         inorderTraverse(t.right);
    * Given an array of unsorted integers
    * adds add the these elements of unsorted as nodes
    * to an initially empty binary search tree
    * @param x is array which it element to be added to a binary tree
    public BinarySearchTree<Integer> numberstoTree(int[] x)
     BinarySearchTree<Integer> treeOne = new BinarySearchTree<Integer>();
     Arrays.sort(x);
     for (int i = 0 ; i < x.length ; i++) {
            int j = x;
     treeOne.insert(j);
     treeOne.inorderTraverse();
     return treeOne;
public void inorderTraverse() {
     inorderTraverse(root);
private void inorderTraverse(BinaryNode<AnyType> t) {
     if (t != null) {
     inorderTraverse(t.left);
     System.out.println(t.elementAt(t));
     inorderTraverse(t.right);
// Test program
public static void main(String[] args)
BinarySearchTree<Integer> t = new BinarySearchTree<Integer>();
final int NUMS = 4000;
final int GAP = 37;
System.out.println("Checking... (no more output means success)");
for( int i = GAP; i != 0; i = ( i + GAP ) % NUMS ) {
t.insert(i);
for(int i = 1; i < NUMS; i += 2) {
t.remove(i);
if(t.findMin().elementAt(t) != 2 || t.findMax().elementAt(t) != NUMS - 2) { //LINE 332 with error
System.out.println("FindMin or FindMax error!");
for(int i = 2; i < NUMS; i += 2) {
     if( t.find(i) != i) {
System.out.println("Find error1!");
for(int i = 1; i < NUMS; i += 2) {
if(t.find(i) != null) {
System.out.println("Find error2!");
}I getting these errors:BinarySearchTree.java:274: operator > cannot be applied to java.lang.Comparable,int
     if(t.elementAt(t) >a && t.elementAt(t) < b) {
^
BinarySearchTree.java:274: operator < cannot be applied to java.lang.Comparable,int
     if(t.elementAt(t) >a && t.elementAt(t) < b) {
^
BinarySearchTree.java:332: elementAt(BinaryNode) in BinarySearchTree cannot be applied to (BinarySearchTree<java.lang.Integer>)
if(t.findMin().elementAt(t) != 2 || t.findMax().elementAt(t) != NUMS - 2) {
^
BinarySearchTree.java:332: cannot find symbol
symbol : method elementAt(BinarySearchTree<java.lang.Integer>)
location: class java.lang.Integer
if(t.findMin().elementAt(t) != 2 || t.findMax().elementAt(t) != NUMS - 2) {
^ I've tried to change the method return types, to integer, AnyType but still producing more or same amount of errors, any help debugging this would be so helpful!.
Thanks

So i've tried to re implement the static statements. i.e
if(t.findMin().compareTo(t.elementAt(t.root)) != 2 || t.findMax().compareTo(t.elementAt(t.root)) != NUMS - 2) {
            System.out.println("FindMin or FindMax error!");
     }but now receiving this error :
BinarySearchTree.java: operator > cannot be applied to java.lang.Comparable,java.lang.Integer
         if(t.elementAt(t) > A && t.elementAt(t) < B) { //LINE 274 WITH ERROR
                              ^
BinarySearchTree.java: operator < cannot be applied to java.lang.Comparable,java.lang.Integer
         if(t.elementAt(t) > A && t.elementAt(t) < B) { //LINE 274 WITH ERROR
                                                    ^
BinarySearchTree.java: cannot find symbol
symbol : method compareTo(java.lang.Integer)
location: class BinaryNode<java.lang.Integer>
        if(t.findMin().compareTo(t.elementAt(t.root)) != 2 || t.findMax().compareTo(t.elementAt(t.root)) != NUMS - 2) {
                    ^
BinarySearchTree.java: cannot find symbol
symbol : method compareTo(java.lang.Integer)
location: class BinaryNode<java.lang.Integer>
        if(t.findMin().compareTo(t.elementAt(t.root)) != 2 || t.findMax().compareTo(t.elementAt(t.root)) != NUMS - 2) {The method compareTo takes an object as defined in the comparable interface which my BinarySearchTree extends. Binary Node is a child of BinarySearchTree. I've been messing around with where i initiate the compareTo method but not had any success, any idea/push in the right direction would be appreciated.
Thanks

I'm just wondering : when a Component Tree is contitute for the first time

When I'm looking at the JSF life cycle figure I can see the "Reconstitute Componente Tree" but I don't see something like "Constitute Componente Tree". When is it supposed to happen ?
Thanks for your answer.

If there is no existing tree (for example if it's the first time you reach a certain page), you start with an empty tree. It is up to you to create a new tree, either directly from Java, or (which is probably going to be the most typical scenario) through a template language like JSP using the Standard HTML RenderKit Tag Library.
When using JSP, the JSF spec defines a sort of tree merging algorithm, which merges an existing tree with a tree defined in your JSP file. If the initial tree is empty, the resulting tree is going to depend 100% on the tree defined in your JSP. If there is an initial tree, slightly more complex rules may apply.

How to delete a node from a node network

How do I delete a node from a node network?
<P>
<OL>
<LI>Follow the instructions on page 30 of the Calendar Server (CS) 3.x Admin Guide,
and page 62 of the CS 4.0 Admin Guide "Deleting (excluding) a Node from the
Network".
<LI>Shut down the Directory Server.
<LI>Backup the LDAP directory to an LDIF file.
<LI>Edit this LDIF file and delete references to the
6 calendar reserved users for the node to be deleted.
<LI>Restore the LDAP directory with this changed LDIF file.
<LI>Run unidbfix -export -n all
<LI>Edit the resulting remotenodes.ini
files and delete all
references to the node to be deleted.
<LI>Run unidbfix -import -n all
<LI>Start the Directory Server.
<LI>Start the Calendar Server.
<P>
Note: This next step is for Calendar Server 3.x * ONLY *
<P>
<LI>Run unireqdump -delete
to delete all requests to the node
to be deleted.
</OL>

Divya wrote:
Hi,
I'm using forms6i.
I want to delete unselected nodes from a tree
How can it be done??
ThanksIf you mean empty branches as unselected nodes,
set Allow Empty Branches property to 'No' in the Trees property.

Designer not incorporating OLB item properties

I have an item identified on a canvas as a tree control item. In the item property Template/Object Library I have the value 'USO$MY_TREE'. In the object library used for generation I have 'USO$MY_TREE' identified and the property 'Allow Empty Branches' set to no. When I generate my form from case and look at it in Forms6I that vale is set to Yes. I am using designer version 6.5.91.0.9 configuration 4.0.12 release 4.6.
Forms Builder version 6.0.8.18.3. I need this to say 'No' which is what is in the Object Library. Is there a generator preference or something I am missing here?

Hi
In the generated FMB, the tree control subclass information is correctly pointing to your object?
Anyway, if there is no other way, you may, in the when-new-form-instance trigger, dynamically set that property:
set_tree_property('block.tree', ALLOW_EMPTY_BRANCHES, PROPERTY_FALSE);
hth

BPM Fork Processing without receiving all required messages

Hi
I am developing a BPM which receives 5 different messages.
I am putting a block with Local Correlation with Block Start = New Transaction and Block End = New Transaction.
Inside this block, I am using Fork with Necessary Branches = 5 , using local correlation for each receive step with Use Correlation and Activate Correlation.
When I am adding Receive Steps to Fork, there is an extra branch getting added to the Fork. So now I have 5 Receive steps with Abstract Interfaces and one extra step without having anything. I couldn't figure out how to get rid of this extra step. I know there is way to get rid of this extra step in Fork...but not sure how
Now, when I am testing, after receiving any 4 messages process is coming out of the Fork block and going to the next block.
As in the next block I use all the 5 messages, I am getting error there.
Can you please give your inputs what could cause this problem?
How do we get rid of extra branch in Fork which we do not use..
Thanks for your help in advance.
Regads,
Ramesh

Hello Ramesh,
When you Drag-Drop any process step in the Fork, it will create a new branch and will sit inside that branch. If you want to put the step on some specific branch then Drag the process step and take it to the desired branch and only drop when [ ] appears on that branch. To insert new branch in fork you can use Right click on Fork->Insert->New Branch.
Now for ur problem, you have set the necessary branches as 5, when u receive the 4 message(4 branches executed) and fifth branch(empty branch) will make total count to 5. Therefore, ur fork step will be executed and will not wait for the fifth msg.
HTH,
Regards,
Sami.

DisclosureIcon on empty branches in Tree

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