Here you can find the source of isWrapperClass(Class> clazz)
public static boolean isWrapperClass(Class<?> clazz)
//package com.java2s; /*/* w ww. j a va2 s . c o m*/ * Copyright (c) 2013 - 2016 Trojaner <trojaner25@gmail.com> and contributors * * 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/>. */ import java.util.HashMap; import java.util.Map; public class Main { public final static Map<Class<?>, Class<?>> primitiveMap = new HashMap<>(); public static boolean isWrapperClass(Class<?> clazz) { return primitiveMap.values().contains(clazz); } }