Here you can find the source of addIfNotEmpty(Collection
public static <T> void addIfNotEmpty(Collection<T> c, Collection<T> elements)
//package com.java2s; /*/*from w ww . ja v a2s .co m*/ * Swordess-ldap, an Object-Directory Mapping tool. * * Copyright (c) 2013, 2013 Liu Xingyu. * * Swordess-ldap is free software: you can redistribute it and/or modify it * under the terms of the GNU Lesser General Public License as published by the * Free Software Foundation, either version 3 of the License, or (at your * option) any later version. * * Swordess-ldap 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 Lesser General Public License * for more details. * * You should have received a copy of the GNU Lesser General Public License * along with Swordess-ldap. If not, see <http://www.gnu.org/licenses/>. */ import java.util.Collection; public class Main { public static <T> void addIfNotEmpty(Collection<T> c, Collection<T> elements) { if (null != c && null != elements && !elements.isEmpty()) { c.addAll(elements); } } public static boolean isEmpty(Collection<?> c) { return null == c || c.isEmpty(); } }