I. Spring Bean Life Cycle logic execution order (from instantiation to destruction)
(instantiated to destruction)
- Loading bean definition (metadata processing)
-
Spring from the
configuration file (@Configuration), XML file or component scan (@Component)- read bean definition.
- This is metadata processing steps , no instance has been created.
- Related method:
-
BeanDefinitionRegistry#registerBeanDefinition()
- Create the actual bean object through the following ways:
The constructive function is instantiated
- Factory method
-
- Related method:
-
Set the bean name
InstantiationAwareBeanPostProcessor#postProcessBeforeInstantiation()
( )
-
, Spring will call
- Method to
- inform Bean's own name
. This happened before before the injection
BeanNameAware#setBeanName(String name)
.- Use case:
- If bean needs to know its name
BeanNameAware
in the context of the application.setBeanName()
- Set the bean class loader () If bean needs to access its class loader
- If bean needs to know its name
public class MyBean implements BeanNameAware { @Override public void setBeanName(String name) { System.out.println("Bean Name Set: " + name); } }If bean
dynamically load the class
- at runtime.
-
BeanClassLoaderAware#setBeanClassLoader(ClassLoader classLoader)
- <置> Set Beanfactory ( )
- Spring Injects Beanfactory into Bean.
Allow bean
public class MyBean implements BeanClassLoaderAware { @Override public void setBeanClassLoader(ClassLoader classLoader) { System.out.println("ClassLoader Set!"); } }by programming.
-
BeanFactoryAware#setBeanFactory(BeanFactory factory)
- <置> Set the environment
- ()
- If bean needs to access environment variables and attributes , this method will be called. <例> Use case: Used to dynamically access the value in
public class MyBean implements BeanFactoryAware { @Override public void setBeanFactory(BeanFactory beanFactory) { System.out.println("BeanFactory Set!"); } }
-
<置> Set the embedded value parser
)EnvironmentAware#setEnvironment(Environment environment)
(- Allowed bean Analyzing the placement of placement ($ {Property}) .
- <例> Usage: When bean needs manually parsing the placeholder is useful.
public class MyBean implements BeanNameAware { @Override public void setBeanName(String name) { System.out.println("Bean Name Set: " + name); } }
-
<置> Set the resource loader ()
ResourceLoaderAware#setResourceLoader(ResourceLoader loader)
- Only applies to
- ApplicationContext for dynamic loading resources. <例> Use case:
- Loading files, class path resources or external resources.
- <置> Set the application event publisher
- (
)
to publish an eventApplicationEventPublisherAware#setApplicationEventPublisher(ApplicationEventPublisher publisher)
If bean needs- , this method will be called.
- <例> Use case: Used for broadcasting events, such as .
-
ContextRefreshedEvent
(
- )
-
If bean needs Internationalization (I18N) to support
MessageSourceAware#setMessageSource(MessageSource source)
, Spring will inject MessageSource. <置> Set ApplicationContext
)
-
If bean needs to access the entire Spring ApplicationContext , this method will be called.
<例> Example:ApplicationContextAware#setApplicationContext(ApplicationContext ctx)
- Allow dynamic access to
- other beans, environmental settings, etc. .
- <置> Set the servertContext
)
- Only applicable to
- Web applications
, used to access the Web context information .
ServletContextAware#setServletContext(ServletContext ctx)
- <始> The post -processing before the initialization (
Allowed
- before bean
- before the
modified bean.
BeanPostProcessor#postProcessBeforeInitialization()
- <定> Customized initialization
- Custom <方法> Method
<的> Custom
-
InitializingBean
afterPropertiesSet()
-
@PostConstruct
<始> After the initialized post -treatment - (
@Bean
)init-method
later -
public class MyBean implements BeanClassLoaderAware { @Override public void setBeanClassLoader(ClassLoader classLoader) { System.out.println("ClassLoader Set!"); } }
<例> Example:
- Used to create proxy, log records or face -oriented programming (AOP)
- .
BeanPostProcessor#postProcessAfterInitialization()
-
bean available - Bean has completely initialized and can be used for applications.
-
<、> 2. Destruction stage (bean close the life cycle)
When the application is closed, Spring will be elegant
destroyed bean.
- <毀> The treatment before destroyed
- (
)
.DestructionAwareBeanPostProcessor#postProcessBeforeDestruction()
Allows to clean up before the destroy Method -
DisposableBean
If bean is implemented,destroy()
will be called.-
DisposableBean
destroy()
Method (preferred method) -
public class MyBean implements BeanNameAware { @Override public void setBeanName(String name) { System.out.println("Bean Name Set: " + name); } }
- is more modern than <現(xiàn)>, and
call before bean destroyed .
@PreDestroy
-
DisposableBean
<定> Custom (If defined in
-
public class MyBean implements BeanClassLoaderAware { @Override public void setBeanClassLoader(ClassLoader classLoader) { System.out.println("ClassLoader Set!"); } }
- Define the alternative method of cleaning the logic.
-
destroy-method
@Bean
Three, the complete process summary (final order)- ? Bean initialization stage
instantiated bean ()
() (
)- ( )
-
new Bean()
( ) -
setBeanName()
(BeanNameAware
) - (
setBeanClassLoader()
)BeanClassLoaderAware
( - )
setBeanFactory()
BeanFactoryAware
( ) -
setEnvironment()
(EnvironmentAware
) - (
setEmbeddedValueResolver()
)EmbeddedValueResolverAware
( - )
setResourceLoader()
ResourceLoaderAware
/ -
setApplicationEventPublisher()
(ApplicationEventPublisherAware
) -
bean available setMessageSource()
MessageSourceAware
-
setApplicationContext()
? Bean's destruction stageApplicationContextAware
-
setServletContext()
(ServletContextAware
) - (
postProcessBeforeInitialization()
)BeanPostProcessor
-
@PostConstruct
afterPropertiesSet()
-
postProcessAfterInitialization()
More information about interface and methods, please visit:BeanPostProcessor
http://www.miracleart.cn/link/6759d0996526ddc8e27aa550F0B806B1 - I wish you a happy coding! ?
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