/*
* Copyright 2002-2014 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;
import org.springframework.beans.factory.HierarchicalBeanFactory;
import org.springframework.beans.factory.ListableBeanFactory;
import org.springframework.beans.factory.config.AutowireCapableBeanFactory;
import org.springframework.core.env.EnvironmentCapable;
import org.springframework.core.io.support.ResourcePatternResolver;
import org.springframework.lang.Nullable;
/**
* Central interface to provide configuration for an application.
* This is read-only while the application is running, but may be
* reloaded if the implementation supports this.
* 为应用程序提供配置的中央接口
* 在应用程序运行时,这是只读的,但是如果实现支持这个接口,则可以重新加载.
*
* <p>An ApplicationContext provides:
* 一个ApplicationContext提供以下的功能:
* <ul>
* <li>Bean factory methods for accessing application components.
* 用于访问应用程序组件的Bean工厂方法.
* Inherited from {@link org.springframework.beans.factory.ListableBeanFactory}.
* <li>The ability to load file resources in a generic fashion.
* 以通用方式加载资源文件的能力
* Inherited from the {@link org.springframework.core.io.ResourceLoader} interface.
* <li>The ability to publish events to registered listeners.
* 将事件发布到注册侦听器的能力
* Inherited from the {@link ApplicationEventPublisher} interface.
* <li>The ability to resolve messages, supporting internationalization.
* 解析消息的能力,支持国际化.
* Inherited from the {@link MessageSource} interface.
* <li>Inheritance from a parent context. Definitions in a descendant context
* will always take priority. This means, for example, that a single parent
* context can be used by an entire web application, while each servlet has
* its own child context that is independent of that of any other servlet.
* 从父上下文继承,在后代上下文中的定义将始终处于优先级.例如,这意味着单个父上下文可以被整个web应用程序使用,
* 而每个servlet都有自己独立于任何其他servlet的子上下文.
* </ul>
*
* <p>In addition to standard {@link org.springframework.beans.factory.BeanFactory}
* lifecycle capabilities, ApplicationContext implementations detect and invoke
* {@link ApplicationContextAware} beans as well as {@link ResourceLoaderAware},
* {@link ApplicationEventPublisherAware} and {@link MessageSourceAware} beans.
* 除了标准的BeanFactory生命周期功能,ApplicationContext实现检测和调用{ApplicationContextAware}bean以及
* {ResourceLoaderAware},{ApplicationEventPublisherAware}和{MessageSourceAware}的beans.
* @author Rod Johnson
* @author Juergen Hoeller
* @see ConfigurableApplicationContext
* @see org.springframework.beans.factory.BeanFactory
* @see org.springframework.core.io.ResourceLoader
*/
public interface ApplicationContext extends EnvironmentCapable, ListableBeanFactory, HierarchicalBeanFactory,
MessageSource, ApplicationEventPublisher, ResourcePatternResolver {
/**
* Return the unique id of this application context.
* 返回此应用程序上下文的唯一id.
* @return the unique id of the context, or {@code null} if none
*/
@Nullable
String getId();
/**
* Return a name for the deployed application that this context belongs to.
* 返回此上下文所属的已部署的应用程序的名称
* @return a name for the deployed application, or the empty String by default
*/
String getApplicationName();
/**
* Return a friendly name for this context.
* 为这个上下文返回一个友好的名称
* @return a display name for this context (never {@code null})
*/
String getDisplayName();
/**
* Return the timestamp when this context was first loaded.
* 返回第一次加载改上下文时的时间戳
* @return the timestamp (ms) when this context was first loaded
*/
long getStartupDate();
/**
* Return the parent context, or {@code null} if there is no parent
* and this is the root of the context hierarchy.
* 返回父上下文,如果没有父上下文,并且这是上下文层次结构的根,则返回{null}
* @return the parent context, or {@code null} if there is no parent
*/
@Nullable
ApplicationContext getParent();
/**
* Expose AutowireCapableBeanFactory functionality for this context.
* 为此上下文公开AutowireCapableBeanFactory的功能
*
* <p>This is not typically used by application code, except for the purpose of
* initializing bean instances that live outside of the application context,
* applying the Spring bean lifecycle (fully or partly) to them.
* 这通常不被应用程序代码使用,除非是为了初始化位于应用程序上下文之外的bean实例.
* 对它们应用Spring bean生命周期(全部或部分).
*
* <p>Alternatively, the internal BeanFactory exposed by the
* {@link ConfigurableApplicationContext} interface offers access to the
* {@link AutowireCapableBeanFactory} interface too. The present method mainly
* serves as a convenient, specific facility on the ApplicationContext interface.
* 另外,由{ConfigurableApplicationContext}接口公开的内部BeanFactory也提供对
* {AutowireCapableBeanFactory}接口的访问.本方法主要用于作为ApplicationContext接口上的一种方便的,特定的工具.
*
* <p><b>NOTE: As of 4.2, this method will consistently throw IllegalStateException
* after the application context has been closed.</b> In current Spring Framework
* versions, only refreshable application contexts behave that way; as of 4.2,
* all application context implementations will be required to comply.
* @return the AutowireCapableBeanFactory for this context
* @throws IllegalStateException if the context does not support the
* {@link AutowireCapableBeanFactory} interface, or does not hold an
* autowire-capable bean factory yet (e.g. if {@code refresh()} has
* never been called), or if the context has been closed already
* @see ConfigurableApplicationContext#refresh()
* @see ConfigurableApplicationContext#getBeanFactory()
* 注意:从4.2版本开始,该方法将在应用程序上下文关闭后始终抛出IllegalStateException
* 在当前的Spring框架版本中,只有可刷新的应用程序上下文才会有这种行为,从4.2开始,
* 所有应用程序上下文都必须遵守.
*/
AutowireCapableBeanFactory getAutowireCapableBeanFactory() throws IllegalStateException;
}
