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/* * Copyright 2002-2019 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.context.annotation; import java.util.function.Supplier; import org.springframework.beans.factory.config.BeanDefinitionCustomizer; import org.springframework.beans.factory.support.BeanNameGenerator; import org.springframework.beans.factory.support.DefaultListableBeanFactory; import org.springframework.context.support.GenericApplicationContext; import org.springframework.core.env.ConfigurableEnvironment; import org.springframework.lang.Nullable; import org.springframework.util.Assert; /** * Standalone application context, accepting annotated classes as input - in particular * {@link Configuration @Configuration}-annotated classes, but also plain * {@link org.springframework.stereotype.Component @Component} types and JSR-330 compliant * classes using {@code javax.inject} annotations. Allows for registering classes one by * one using {@link #register(Class...)} as well as for classpath scanning using * {@link #scan(String...)}. * * <p>In case of multiple {@code @Configuration} classes, @{@link Bean} methods defined in * later classes will override those defined in earlier classes. This can be leveraged to * deliberately override certain bean definitions via an extra {@code @Configuration} * class. * * <p>See @{@link Configuration}'s javadoc for usage examples. * * @author Juergen Hoeller * @author Chris Beams * @since 3.0 * @see #register * @see #scan * @see AnnotatedBeanDefinitionReader * @see ClassPathBeanDefinitionScanner * @see org.springframework.context.support.GenericXmlApplicationContext */ public class AnnotationConfigApplicationContext extends GenericApplicationContext implements AnnotationConfigRegistry { private final AnnotatedBeanDefinitionReader reader; private final ClassPathBeanDefinitionScanner scanner; /** * Create a new AnnotationConfigApplicationContext that needs to be populated * through {@link #register} calls and then manually {@linkplain #refresh refreshed}. */ public AnnotationConfigApplicationContext() { this.reader = new AnnotatedBeanDefinitionReader(this); this.scanner = new ClassPathBeanDefinitionScanner(this); } /** * Create a new AnnotationConfigApplicationContext with the given DefaultListableBeanFactory. * @param beanFactory the DefaultListableBeanFactory instance to use for this context */ public AnnotationConfigApplicationContext(DefaultListableBeanFactory beanFactory) { super(beanFactory); this.reader = new AnnotatedBeanDefinitionReader(this); this.scanner = new ClassPathBeanDefinitionScanner(this); } /** * Create a new AnnotationConfigApplicationContext, deriving bean definitions * from the given annotated classes and automatically refreshing the context. * @param annotatedClasses one or more annotated classes, * e.g. {@link Configuration @Configuration} classes */ public AnnotationConfigApplicationContext(Class<?>... annotatedClasses) { this(); register(annotatedClasses); refresh(); } /** * Create a new AnnotationConfigApplicationContext, scanning for bean definitions * in the given packages and automatically refreshing the context. * @param basePackages the packages to check for annotated classes */ public AnnotationConfigApplicationContext(String... basePackages) { this(); scan(basePackages); refresh(); } /** * Propagates the given custom {@code Environment} to the underlying * {@link AnnotatedBeanDefinitionReader} and {@link ClassPathBeanDefinitionScanner}. */ @Override public void setEnvironment(ConfigurableEnvironment environment) { super.setEnvironment(environment); this.reader.setEnvironment(environment); this.scanner.setEnvironment(environment); } /** * Provide a custom {@link BeanNameGenerator} for use with {@link AnnotatedBeanDefinitionReader} * and/or {@link ClassPathBeanDefinitionScanner}, if any. * <p>Default is {@link org.springframework.context.annotation.AnnotationBeanNameGenerator}. * <p>Any call to this method must occur prior to calls to {@link #register(Class...)} * and/or {@link #scan(String...)}. * @see AnnotatedBeanDefinitionReader#setBeanNameGenerator * @see ClassPathBeanDefinitionScanner#setBeanNameGenerator */ public void setBeanNameGenerator(BeanNameGenerator beanNameGenerator) { this.reader.setBeanNameGenerator(beanNameGenerator); this.scanner.setBeanNameGenerator(beanNameGenerator); getBeanFactory().registerSingleton(AnnotationConfigUtils.CONFIGURATION_BEAN_NAME_GENERATOR, beanNameGenerator); } /** * Set the {@link ScopeMetadataResolver} to use for detected bean classes. * <p>The default is an {@link AnnotationScopeMetadataResolver}. * <p>Any call to this method must occur prior to calls to {@link #register(Class...)} * and/or {@link #scan(String...)}. */ public void setScopeMetadataResolver(ScopeMetadataResolver scopeMetadataResolver) { this.reader.setScopeMetadataResolver(scopeMetadataResolver); this.scanner.setScopeMetadataResolver(scopeMetadataResolver); } //--------------------------------------------------------------------- // Implementation of AnnotationConfigRegistry //--------------------------------------------------------------------- /** * Register one or more annotated classes to be processed. * <p>Note that {@link #refresh()} must be called in order for the context * to fully process the new classes. * @param annotatedClasses one or more annotated classes, * e.g. {@link Configuration @Configuration} classes * @see #scan(String...) * @see #refresh() */ public void register(Class<?>... annotatedClasses) { Assert.notEmpty(annotatedClasses, "At least one annotated class must be specified"); this.reader.register(annotatedClasses); } /** * Perform a scan within the specified base packages. * <p>Note that {@link #refresh()} must be called in order for the context * to fully process the new classes. * @param basePackages the packages to check for annotated classes * @see #register(Class...) * @see #refresh() */ public void scan(String... basePackages) { Assert.notEmpty(basePackages, "At least one base package must be specified"); this.scanner.scan(basePackages); } //--------------------------------------------------------------------- // Adapt superclass registerBean calls to AnnotatedBeanDefinitionReader //--------------------------------------------------------------------- @Override public <T> void registerBean(@Nullable String beanName, Class<T> beanClass, @Nullable Supplier<T> supplier, BeanDefinitionCustomizer... customizers) { this.reader.registerBean(beanClass, beanName, supplier, customizers); } }