001/*
002 * Copyright 2002-2018 the original author or authors.
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 *      https://www.apache.org/licenses/LICENSE-2.0
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016
017package org.springframework.beans.factory.support;
018
019import java.lang.reflect.Constructor;
020import java.lang.reflect.Method;
021
022import org.springframework.beans.BeansException;
023import org.springframework.beans.factory.BeanFactory;
024import org.springframework.lang.Nullable;
025
026/**
027 * Interface responsible for creating instances corresponding to a root bean definition.
028 *
029 * <p>This is pulled out into a strategy as various approaches are possible,
030 * including using CGLIB to create subclasses on the fly to support Method Injection.
031 *
032 * @author Rod Johnson
033 * @author Juergen Hoeller
034 * @since 1.1
035 */
036public interface InstantiationStrategy {
037
038        /**
039         * Return an instance of the bean with the given name in this factory.
040         * @param bd the bean definition
041         * @param beanName the name of the bean when it is created in this context.
042         * The name can be {@code null} if we are autowiring a bean which doesn't
043         * belong to the factory.
044         * @param owner the owning BeanFactory
045         * @return a bean instance for this bean definition
046         * @throws BeansException if the instantiation attempt failed
047         */
048        Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner)
049                        throws BeansException;
050
051        /**
052         * Return an instance of the bean with the given name in this factory,
053         * creating it via the given constructor.
054         * @param bd the bean definition
055         * @param beanName the name of the bean when it is created in this context.
056         * The name can be {@code null} if we are autowiring a bean which doesn't
057         * belong to the factory.
058         * @param owner the owning BeanFactory
059         * @param ctor the constructor to use
060         * @param args the constructor arguments to apply
061         * @return a bean instance for this bean definition
062         * @throws BeansException if the instantiation attempt failed
063         */
064        Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner,
065                        Constructor<?> ctor, Object... args) throws BeansException;
066
067        /**
068         * Return an instance of the bean with the given name in this factory,
069         * creating it via the given factory method.
070         * @param bd the bean definition
071         * @param beanName the name of the bean when it is created in this context.
072         * The name can be {@code null} if we are autowiring a bean which doesn't
073         * belong to the factory.
074         * @param owner the owning BeanFactory
075         * @param factoryBean the factory bean instance to call the factory method on,
076         * or {@code null} in case of a static factory method
077         * @param factoryMethod the factory method to use
078         * @param args the factory method arguments to apply
079         * @return a bean instance for this bean definition
080         * @throws BeansException if the instantiation attempt failed
081         */
082        Object instantiate(RootBeanDefinition bd, @Nullable String beanName, BeanFactory owner,
083                        @Nullable Object factoryBean, Method factoryMethod, Object... args)
084                        throws BeansException;
085
086}