Here you can find the source of assertIndex(final String s, final int index)
static private int assertIndex(final String s, final int index)
//package com.java2s; /**// ww w.j a va2 s . com Copyright (C) SYSTAP, LLC 2006-2011. All rights reserved. Contact: SYSTAP, LLC 4501 Tower Road Greensboro, NC 27410 licenses@bigdata.com 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; version 2 of the License. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ public class Main { static private int assertIndex(final String s, final int index) { if (index >= 0) return index; throw new IllegalArgumentException(s); } }