Finding all possible combinations of a String using recursion - Full Java Code

/**
 *  $Id: StringCombinations.java 100 2010-03-13 23:12:20Z oneyour $
 * 
 * This is an accompanying program for the article
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" title="http://www.1your.com/drupal/FullCodeFindingAllStringCombinationsUsingRecursion
">http://www.1your.com/drupal/FullCodeFindingAllStringCombinationsUsingRec...</a> * 
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import java.io.IOException;
import java.util.HashSet;
import java.util.Scanner;
import java.util.Set;
 
/**
* A simple program that generates all possible combinations for a given
* String using recursion.
*
*/
public class StringCombinations
{
    // A set to hold the generated combination results.
    private Set combinations = new HashSet();
 
    /**
    * The constructor.
    *
    * Simply makes a call to the generate method
    * to generate all the possible combinations of the
    * String "wxyz"
    */
    public StringCombinations(String sInputString)
    {
        generate(sInputString);
        System.out.println("*** Generated " + combinations .size() + " combinations ***");
        System.out.println(combinations);
        System.out.println("Visit <a href="http://www.1your.com" title="www.1your.com">www.1your.com</a> for more Java articles");
        System.out.println("Whats even more great is you can request for articles and" +
        "see articles created just for your request!");
    }
 
    /**
    * The recursive method does the work of generating all the possible
    * combinations for a given String.
    */
    public void generate(String word)
    {
        // Add this word to our combination results set
        // System.out.println(word);
        combinations.add(word);
 
        // If the word has only one character we break the
        // recursion
        if (word.length() == 1)
        {
            combinations.add(word);
            return;
        }
 
        // Go through every position of the word
        for (int i = 0; i < word.length(); i++)
        {
            // Remove the character at the current position
            // all call this method with that String (Recursion!)
            generate(word.substring(0,i) + word.substring(i+1));
        }
    }
 
 
    /**
     * Request and read input from the command line (System.in)
     * 
     * @param inputMessage
     *      The message to be displayed as a request to the user
     *      
     * @return
     *      The input from the command line
     *      
     * @throws IOException
     *      Any problems while reading the input
     */
    public static String readCommandLineInput(String inputMessage)
    {
        System.out.println(inputMessage);
        Scanner scanner = new Scanner(System.in);
 
        String inputLine = scanner.nextLine();
        return inputLine;
    }
 
    /**
    * Entry point to this program.
    * Instantiates the StringCombinations program.
    *
    */
    public static void main(String args[])
    {
		// Request and read user input
		String sInstruction = "Enter a String: \n";
		String sInputString = readCommandLineInput(sInstruction);
        new StringCombinations(sInputString);
    }
 
}// End of StringCombinations