Demonstrate TreeSet

package com.darwinsys;
 
/*
 * Copyright (c) Ian F. Darwin, http://www.darwinsys.com/, 1996-2002.
 * All rights reserved. Software written by Ian F. Darwin and others.
 * $Id: LICENSE,v 1.8 2004/02/09 03:33:38 ian Exp $
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS''
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 * 
 * Java, the Duke mascot, and all variants of Sun's Java "steaming coffee
 * cup" logo are trademarks of Sun Microsystems. Sun's, and James Gosling's,
 * pioneering role in inventing and promulgating (and standardizing) the Java 
 * language and environment is gratefully acknowledged.
 * 
 * The pioneering role of Dennis Ritchie and Bjarne Stroustrup, of AT&T, for
 * inventing predecessor languages C and C++ is also gratefully acknowledged.
 */
 
import java.util.TreeSet;
 
/**
 * TreeSet Demo.
 * 
 * @author Ian F. Darwin, http://www.darwinsys.com/
 * @version $Id: TreeSetDemo.java,v 1.3 2004/02/09 03:34:04 ian Exp $
 */
public class TreeSetDemo {
    public static void main(String[] argv) {
	// +
	/*
	 * A TreeSet keeps objects in sorted order. We use a Comparator published by String for case-insensitive sorting order.
	 */
	TreeSet tm = new TreeSet(String.CASE_INSENSITIVE_ORDER);
	tm.add("Gosling");
	tm.add("da Vinci");
	tm.add("van Gogh");
	tm.add("Java To Go");
	tm.add("Vanguard");
	tm.add("Darwin");
	tm.add("Darwin"); // TreeSet is Set, ignores duplicates.
 
	// Since it is sorted we can ask for various subsets
	System.out.println("Lowest (alphabetically) is " + tm.first());
	// Print how many elements are greater than "k"
	System.out.println(tm.tailSet("k").toArray().length + " elements higher than \"k\"");
 
	// Print the whole list in sorted order
	System.out.println("Sorted list:");
	java.util.Iterator t = tm.iterator();
	while (t.hasNext())
	    System.out.println(t.next());
	// -
    }
}