1 /* 2 * Grapht, an open source dependency injector. 3 * Copyright 2014-2015 various contributors (see CONTRIBUTORS.txt) 4 * Copyright 2010-2014 Regents of the University of Minnesota 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU Lesser General Public License as 8 * published by the Free Software Foundation; either version 2.1 of the 9 * License, or (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, but WITHOUT 12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS 13 * FOR A PARTICULAR PURPOSE. See the GNU General Public License for more 14 * details. 15 * 16 * You should have received a copy of the GNU General Public License along with 17 * this program; if not, write to the Free Software Foundation, Inc., 51 18 * Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. 19 */ 20 package org.grouplens.grapht.reflect; 21 22 import javax.inject.Provider; 23 24 /** 25 * An interface for visiting {@link Satisfaction}s. 26 * 27 * @param <T> The type returned from this satisfaction's values. 28 * @author <a href="http://grouplens.org">GroupLens Research</a> 29 * @since 0.5 30 * @see Satisfaction 31 */ 32 public interface SatisfactionVisitor<T> { 33 /** 34 * Called when visiting a null satisfaction. 35 * 36 * @return The return value. 37 */ 38 T visitNull(); 39 40 /** 41 * Called when visiting a satisfaction that will instantiate a class. 42 * 43 * @param clazz The implementation class. 44 * @return The return value. 45 */ 46 T visitClass(Class<?> clazz); 47 48 /** 49 * Called when visiting a satisfaction that will return a pre-configured instance. 50 * 51 * @param instance The instance that will be returned. The visitor should not modify it 52 * in any way. 53 * @return The return value. 54 */ 55 T visitInstance(Object instance); 56 57 /** 58 * Called when visiting a satisfaction that will instantiate and invoke a provider class. 59 * 60 * @param pclass The provider class. 61 * @return The return value. 62 */ 63 T visitProviderClass(Class<? extends Provider<?>> pclass); 64 65 /** 66 * Called when visiting a satisfaction that will invoke a pre-instantiated provider. 67 * 68 * @param provider The provider instance. The visitor should not modify it in any way. 69 * @return The return value. 70 */ 71 T visitProviderInstance(Provider<?> provider); 72 }