Here you can find the source of firstOf(final Iterable
public static <T> T firstOf(final Iterable<T> iterable)
//package com.java2s; /******************************************************************************* * Copyright 2015/* ww w .j a va2s . c o m*/ * Ubiquitous Knowledge Processing (UKP) Lab * Technische Universit?t Darmstadt * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. ******************************************************************************/ import java.util.Iterator; public class Main { public static <T> T firstOf(final Iterable<T> iterable) { return nthOf(iterable, 0); } /** * Retrieves the nth element by linear search. * * The first element has index 0. * * @param iterable the iterable * @param n the 0-based index * @return the item */ public static <T> T nthOf(final Iterable<T> iterable, final int n) { final Iterator<T> iter = iterable.iterator(); for (int i = 0; i < n; ++i) { iter.next(); } return iter.next(); } }