Here you can find the source of arrayFirstIndexOf(final T[] array, final T value)
public static final <T> int arrayFirstIndexOf(final T[] array, final T value)
//package com.java2s; /*// w ww. j av a2s. c o m * 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 3 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, see <http://www.gnu.org/licenses/>. */ public class Main { public static final <T> int arrayFirstIndexOf(final T[] array, final T value) { for (int i = 0; i < array.length; i++) { if (value == array[i]) return i; } return -1; } }