Here you can find the source of hashCode(Object... fields)
public static int hashCode(Object... fields)
//package com.java2s; /*/* www. j a v a2 s . c om*/ * #%~ * VDM Code Generator Runtime * %% * Copyright (C) 2008 - 2014 Overture * %% * 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/gpl-3.0.html>. * #~% */ public class Main { public static int hashCode(Object... fields) { if (fields == null) throw new IllegalArgumentException("Fields cannot be null"); int hashcode = 0; for (int i = 0; i < fields.length; i++) { Object currentField = fields[i]; hashcode += currentField != null ? currentField.hashCode() : 0; } return hashcode; } }