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Number of child in root node of JTree

SoonAnn Lim
Ranch Hand

Joined: Jun 21, 2001
Posts: 155
Hi all,
I am not very clear how the child nodes are handled in JTree. I have a JTree and i obtain the tree model using JTree.getModel() method. TreeModel in turns get me the root node of the Tree using TreeModel.getRoot() method. I do a getChildCount to obtain number of child nodes. If i want to delete all child nodes, i am not able to use a for loop to do that because everytime i use TreeModel.getChild(rootNode, index) and removeNodeFromParent() to get and remove a child from root node, the array of child nodes shrinks automatically, like you are pulling a book at the bottom of a pile of books. So if i want to delete all child nodes, i have to getChild at index=0 for as many times as the child count. Is this the typical way to delete all child nodes?
Rene Liebmann
Ranch Hand

Joined: May 02, 2002
Posts: 196
there is of course another way to remove all children. You can cast the root node to a DefaultMutableTreeNode. with this you can do it.
TreeModel model = tree.getModel();
DefaultMutableTreeNode root = (DefaultMutableTreeNode) model.getRoot();
I agree. Here's the link:
subject: Number of child in root node of JTree
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