Here you can find the source of unionAdd(Vector vect, Object obj)
This method adds obj to vect if and only if vect does not already contain obj.
public static void unionAdd(Vector vect, Object obj)
//package com.java2s; /*/* ww w . j a v a 2 s. co m*/ VectorUtils.java Convenience methods for working with Vectors.. provides efficient Union, Intersection, and Difference methods. Created: 21 July 1998 Release: $Name: $ Version: $Revision: 1.21 $ Last Mod Date: $Date: 2002/11/01 02:25:10 $ Module By: Jonathan Abbey, jonabbey@arlut.utexas.edu ----------------------------------------------------------------------- Ganymede Directory Management System Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002 The University of Texas at Austin. Contact information Web site: http://www.arlut.utexas.edu/gash2 Author Email: ganymede_author@arlut.utexas.edu Email mailing list: ganymede@arlut.utexas.edu US Mail: Computer Science Division Applied Research Laboratories The University of Texas at Austin PO Box 8029, Austin TX 78713-8029 Telephone: (512) 835-3200 This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. */ import java.util.*; public class Main { /** * <P>This method adds obj to vect if and only if vect does not * already contain obj.</P> */ public static void unionAdd(Vector vect, Object obj) { if (obj == null) { return; } if (vect.contains(obj)) { return; } vect.addElement(obj); } }