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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.beans.factory.config; import org.springframework.beans.BeanMetadataElement; import org.springframework.beans.MutablePropertyValues; import org.springframework.core.AttributeAccessor; import org.springframework.core.ResolvableType; import org.springframework.lang.Nullable; /** * A BeanDefinition describes a bean instance, which has property values, * constructor argument values, and further information supplied by * concrete implementations. * * <p>This is just a minimal interface: The main intention is to allow a * {@link BeanFactoryPostProcessor} to introspect and modify property values * and other bean metadata. * * @author Juergen Hoeller * @author Rob Harrop * @since 19.03.2004 * @see ConfigurableListableBeanFactory#getBeanDefinition * @see org.springframework.beans.factory.support.RootBeanDefinition * @see org.springframework.beans.factory.support.ChildBeanDefinition */ public interface BeanDefinition extends AttributeAccessor, BeanMetadataElement { /** * Scope identifier for the standard singleton scope: "singleton". * <p>Note that extended bean factories might support further scopes. * @see #setScope */ String SCOPE_SINGLETON = ConfigurableBeanFactory.SCOPE_SINGLETON; /** * Scope identifier for the standard prototype scope: "prototype". * <p>Note that extended bean factories might support further scopes. * @see #setScope */ String SCOPE_PROTOTYPE = ConfigurableBeanFactory.SCOPE_PROTOTYPE; /** * Role hint indicating that a {@code BeanDefinition} is a major part * of the application. Typically corresponds to a user-defined bean. */ int ROLE_APPLICATION = 0; /** * Role hint indicating that a {@code BeanDefinition} is a supporting * part of some larger configuration, typically an outer * {@link org.springframework.beans.factory.parsing.ComponentDefinition}. * {@code SUPPORT} beans are considered important enough to be aware * of when looking more closely at a particular * {@link org.springframework.beans.factory.parsing.ComponentDefinition}, * but not when looking at the overall configuration of an application. */ int ROLE_SUPPORT = 1; /** * Role hint indicating that a {@code BeanDefinition} is providing an * entirely background role and has no relevance to the end-user. This hint is * used when registering beans that are completely part of the internal workings * of a {@link org.springframework.beans.factory.parsing.ComponentDefinition}. */ int ROLE_INFRASTRUCTURE = 2; // Modifiable attributes /** * Set the name of the parent definition of this bean definition, if any. */ void setParentName(@Nullable String parentName); /** * Return the name of the parent definition of this bean definition, if any. */ @Nullable String getParentName(); /** * Specify the bean class name of this bean definition. * <p>The class name can be modified during bean factory post-processing, * typically replacing the original class name with a parsed variant of it. * @see #setParentName * @see #setFactoryBeanName * @see #setFactoryMethodName */ void setBeanClassName(@Nullable String beanClassName); /** * Return the current bean class name of this bean definition. * <p>Note that this does not have to be the actual class name used at runtime, in * case of a child definition overriding/inheriting the class name from its parent. * Also, this may just be the class that a factory method is called on, or it may * even be empty in case of a factory bean reference that a method is called on. * Hence, do <i>not</i> consider this to be the definitive bean type at runtime but * rather only use it for parsing purposes at the individual bean definition level. * @see #getParentName() * @see #getFactoryBeanName() * @see #getFactoryMethodName() */ @Nullable String getBeanClassName(); /** * Override the target scope of this bean, specifying a new scope name. * @see #SCOPE_SINGLETON * @see #SCOPE_PROTOTYPE */ void setScope(@Nullable String scope); /** * Return the name of the current target scope for this bean, * or {@code null} if not known yet. */ @Nullable String getScope(); /** * Set whether this bean should be lazily initialized. * <p>If {@code false}, the bean will get instantiated on startup by bean * factories that perform eager initialization of singletons. */ void setLazyInit(boolean lazyInit); /** * Return whether this bean should be lazily initialized, i.e. not * eagerly instantiated on startup. Only applicable to a singleton bean. */ boolean isLazyInit(); /** * Set the names of the beans that this bean depends on being initialized. * The bean factory will guarantee that these beans get initialized first. */ void setDependsOn(@Nullable String... dependsOn); /** * Return the bean names that this bean depends on. */ @Nullable String[] getDependsOn(); /** * Set whether this bean is a candidate for getting autowired into some other bean. * <p>Note that this flag is designed to only affect type-based autowiring. * It does not affect explicit references by name, which will get resolved even * if the specified bean is not marked as an autowire candidate. As a consequence, * autowiring by name will nevertheless inject a bean if the name matches. */ void setAutowireCandidate(boolean autowireCandidate); /** * Return whether this bean is a candidate for getting autowired into some other bean. */ boolean isAutowireCandidate(); /** * Set whether this bean is a primary autowire candidate. * <p>If this value is {@code true} for exactly one bean among multiple * matching candidates, it will serve as a tie-breaker. */ void setPrimary(boolean primary); /** * Return whether this bean is a primary autowire candidate. */ boolean isPrimary(); /** * Specify the factory bean to use, if any. * This the name of the bean to call the specified factory method on. * @see #setFactoryMethodName */ void setFactoryBeanName(@Nullable String factoryBeanName); /** * Return the factory bean name, if any. */ @Nullable String getFactoryBeanName(); /** * Specify a factory method, if any. This method will be invoked with * constructor arguments, or with no arguments if none are specified. * The method will be invoked on the specified factory bean, if any, * or otherwise as a static method on the local bean class. * @see #setFactoryBeanName * @see #setBeanClassName */ void setFactoryMethodName(@Nullable String factoryMethodName); /** * Return a factory method, if any. */ @Nullable String getFactoryMethodName(); /** * Return the constructor argument values for this bean. * <p>The returned instance can be modified during bean factory post-processing. * @return the ConstructorArgumentValues object (never {@code null}) */ ConstructorArgumentValues getConstructorArgumentValues(); /** * Return if there are constructor argument values defined for this bean. * @since 5.0.2 */ default boolean hasConstructorArgumentValues() { return !getConstructorArgumentValues().isEmpty(); } /** * Return the property values to be applied to a new instance of the bean. * <p>The returned instance can be modified during bean factory post-processing. * @return the MutablePropertyValues object (never {@code null}) */ MutablePropertyValues getPropertyValues(); /** * Return if there are property values values defined for this bean. * @since 5.0.2 */ default boolean hasPropertyValues() { return !getPropertyValues().isEmpty(); } /** * Set the name of the initializer method. * @since 5.1 */ void setInitMethodName(@Nullable String initMethodName); /** * Return the name of the initializer method. * @since 5.1 */ @Nullable String getInitMethodName(); /** * Set the name of the destroy method. * @since 5.1 */ void setDestroyMethodName(@Nullable String destroyMethodName); /** * Return the name of the destroy method. * @since 5.1 */ @Nullable String getDestroyMethodName(); /** * Set the role hint for this {@code BeanDefinition}. The role hint * provides the frameworks as well as tools with an indication of * the role and importance of a particular {@code BeanDefinition}. * @since 5.1 * @see #ROLE_APPLICATION * @see #ROLE_SUPPORT * @see #ROLE_INFRASTRUCTURE */ void setRole(int role); /** * Get the role hint for this {@code BeanDefinition}. The role hint * provides the frameworks as well as tools with an indication of * the role and importance of a particular {@code BeanDefinition}. * @see #ROLE_APPLICATION * @see #ROLE_SUPPORT * @see #ROLE_INFRASTRUCTURE */ int getRole(); /** * Set a human-readable description of this bean definition. * @since 5.1 */ void setDescription(@Nullable String description); /** * Return a human-readable description of this bean definition. */ @Nullable String getDescription(); // Read-only attributes /** * Return a resolvable type for this bean definition, * based on the bean class or other specific metadata. * <p>This is typically fully resolved on a runtime-merged bean definition * but not necessarily on a configuration-time definition instance. * @return the resolvable type (potentially {@link ResolvableType#NONE}) * @since 5.2 * @see ConfigurableBeanFactory#getMergedBeanDefinition */ ResolvableType getResolvableType(); /** * Return whether this a <b>Singleton</b>, with a single, shared instance * returned on all calls. * @see #SCOPE_SINGLETON */ boolean isSingleton(); /** * Return whether this a <b>Prototype</b>, with an independent instance * returned for each call. * @since 3.0 * @see #SCOPE_PROTOTYPE */ boolean isPrototype(); /** * Return whether this bean is "abstract", that is, not meant to be instantiated. */ boolean isAbstract(); /** * Return a description of the resource that this bean definition * came from (for the purpose of showing context in case of errors). */ @Nullable String getResourceDescription(); /** * Return the originating BeanDefinition, or {@code null} if none. * Allows for retrieving the decorated bean definition, if any. * <p>Note that this method returns the immediate originator. Iterate through the * originator chain to find the original BeanDefinition as defined by the user. */ @Nullable BeanDefinition getOriginatingBeanDefinition(); }