Here you can find the source of as(Object cst)
@SuppressWarnings("unchecked") public static <T> T as(Object cst)
//package com.java2s; /*//from w w w .j av a 2s . 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 { @SuppressWarnings("unchecked") public static <T> T as(Class<T> t, Object cst) { return (T) cst; } @SuppressWarnings("unchecked") public static <T> T as(Object cst) { return (T) cst; } }