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Author : Paul Hamaker. Part of JavaLessons.com
We want to make a JTree,...
but first we have to create its stem and branches.
After setting up the tree-structure, we construct the JTree...
with the DefaultMutableTreeNode stem as argument.
By defining this method...
this class implements javax.swing.event.TreeSelectionListener,...
and, as such, it can be notified when the user makes a selection in the tree.
When the user selects, the JTree is asked for the selection and this is shown as a String.
Insert as first node.