001 /* 002 * Copyright (C) 2012 eXo Platform SAS. 003 * 004 * This is free software; you can redistribute it and/or modify it 005 * under the terms of the GNU Lesser General Public License as 006 * published by the Free Software Foundation; either version 2.1 of 007 * the License, or (at your option) any later version. 008 * 009 * This software is distributed in the hope that it will be useful, 010 * but WITHOUT ANY WARRANTY; without even the implied warranty of 011 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 012 * Lesser General Public License for more details. 013 * 014 * You should have received a copy of the GNU Lesser General Public 015 * License along with this software; if not, write to the Free 016 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 017 * 02110-1301 USA, or see the FSF site: http://www.fsf.org. 018 */ 019 package org.crsh.cli.impl.lang; 020 021 /** 022 * @author Julien Viet 023 */ 024 public interface Instance<T> { 025 026 /** 027 * Resolve the specified contextual type to an instance or return null if no object able 028 * to satisfy the class type was resolved. 029 * 030 * @param type the type to resolve 031 * @param <T> the generic type parameter 032 * @return the resolved instance 033 */ 034 <T> T resolve(Class<T> type); 035 036 /** 037 * Return the instance, the same instance should be returned, however it can lazily be created. 038 * 039 * @return the instance 040 * @throws Exception any exception preventing to obtain the instance 041 */ 042 T get() throws Exception; 043 044 }