Trees and nodes

If you are unfamiliar with this data structure, you should look up some book in classical data structures. A www search like "tree structures in Java" would also give you something to look at.

Secondly, you would have to look at the Java classes of the data structure. They are located in the javax.swing.tree package, and some of the important classes and interfaces to study include javax.swing.tree.TreeNode, javax.swing.tree.DefaultMutableTreeNode, javax.swing.tree.TreeModel and javax.swing.tree.DefaultTreeModel.

Now, try to use these classes. It should not be many lines of codes, just instantiate three or four DefaultMutableTreeNode objects with any string values and construct some tree structure. Finally, you may add the root node of your tree to a DefaultTreeModel object.

TestTree.java

It would now be nice if you could visualize your tree, and in fact there is convenient Swing class to do so called JTree in the javax.swing package. You simply need to add your tree model object to the JTree class, and layout object on a JFrame. In no time you'll have a "directory like" visualizations of your tree structure.

TestJTree.java

The JTree class and the javaw.swing.tree offers lots of customization through many action and change events and GUI setup. Do play with some of this possibilities to get more acquainted to the tree structure and the classes.