Java tutorial
//package com.java2s; /******************************************************************************* * Breakout Cave Survey Visualizer * * Copyright (C) 2014 James Edwards * * jedwards8 at fastmail dot fm * * 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., * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. *******************************************************************************/ import java.util.Collections; import java.util.List; public class Main { public static <T> List<T> nullTolerantUnmodifiableList(List<? extends T> l) { return l == null ? Collections.<T>emptyList() : Collections.unmodifiableList(l); } }