javax.swing.tree
Interface TreeModel

All Known Implementing Classes:

DefaultTreeModel

public interface TreeModel

The interface that defines a suitable data model for a JTree. For further information on tree models, including an example of a custom implementation, see How to Use Trees in The Java Tutorial.

JTree and its related classes make extensive use of TreePaths for indentifying nodes in the TreeModel. If a TreeModel returns the same object, as compared by equals, at two different indices under the same parent than the resulting TreePath objects will be considered equal as well. Some implementations may assume that if two TreePaths are equal, they identify the same node. If this condition is not met, painting problems and other oddities may result. In other words, if getChild for a given parent returns the same Object (as determined by equals) problems may result, and it is recommended you avoid doing this.

See Also:

TreePath

Method Summary

void	addTreeModelListener(TreeModelListener l) Adds a listener for the TreeModelEvent posted after the tree changes.
Object	getChild(Object parent, int index) Returns the child of parent at index index in the parent's child array.
int	getChildCount(Object parent) Returns the number of children of parent.
int	getIndexOfChild(Object parent, Object child) Returns the index of child in parent.
Object	getRoot() Returns the root of the tree.
boolean	isLeaf(Object node) Returns true if node is a leaf.
void	removeTreeModelListener(TreeModelListener l) Removes a listener previously added with addTreeModelListener.
void	valueForPathChanged(TreePath path, Object newValue) Messaged when the user has altered the value for the item identified by path to newValue.

Method Detail

getRoot

Object getRoot()

Returns the root of the tree. Returns null only if the tree has no nodes.

Returns:

the root of the tree

getChild

Object getChild(