Here you can find the source of as(Object value, Class
public static <T> T as(Object value, Class<T> c)
//package com.java2s; /*/*from www . j av a 2 s . c o m*/ Copyright (c) 2009-2011 Olivier Chafik, All Rights Reserved This file is part of JNAerator (http://jnaerator.googlecode.com/). JNAerator 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. JNAerator 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 JNAerator. If not, see <http://www.gnu.org/licenses/>. */ public class Main { public static <T> T as(Object value, Class<T> c) { if (value == null) return null; if (c.isAssignableFrom(value.getClass())) return c.cast(value); return null; } }