org.springframework.web.servlet.handler

Class SimpleServletPostProcessor

java.lang.Object

org.springframework.web.servlet.handler.SimpleServletPostProcessor

All Implemented Interfaces:

Aware, BeanPostProcessor, DestructionAwareBeanPostProcessor, ServletConfigAware, ServletContextAware

public class SimpleServletPostProcessor
extends java.lang.Object
implements DestructionAwareBeanPostProcessor, ServletContextAware, ServletConfigAware

BeanPostProcessor that applies initialization and destruction callbacks to beans that implement the Servlet interface.

After initialization of the bean instance, the Servlet init method will be called with a ServletConfig that contains the bean name of the Servlet and the ServletContext that it is running in.

Before destruction of the bean instance, the Servlet destroy will be called.

Note that this post-processor does not support Servlet initialization parameters. Bean instances that implement the Servlet interface are supposed to be configured like any other Spring bean, that is, through constructor arguments or bean properties.

For reuse of a Servlet implementation in a plain Servlet container and as a bean in a Spring context, consider deriving from Spring's HttpServletBean base class that applies Servlet initialization parameters as bean properties, supporting both the standard Servlet and the Spring bean initialization style.

Alternatively, consider wrapping a Servlet with Spring's ServletWrappingController. This is particularly appropriate for existing Servlet classes, allowing to specify Servlet initialization parameters etc.

Since:

1.1.5

Author:

Juergen Hoeller

See Also:

Servlet.init(javax.servlet.ServletConfig), Servlet.destroy(), SimpleServletHandlerAdapter

Constructor Summary

Constructors

Constructor and Description
SimpleServletPostProcessor()

Method Summary

Modifier and Type	Method and Description
java.lang.Object	postProcessAfterInitialization(java.lang.Object bean, java.lang.String beanName) Apply this BeanPostProcessor to the given new bean instance after any bean initialization callbacks (like InitializingBean's afterPropertiesSet or a custom init-method).
void	postProcessBeforeDestruction(java.lang.Object bean, java.lang.String beanName) Apply this BeanPostProcessor to the given bean instance before its destruction.
java.lang.Object	postProcessBeforeInitialization(java.lang.Object bean, java.lang.String beanName) Apply this BeanPostProcessor to the given new bean instance before any bean initialization callbacks (like InitializingBean's afterPropertiesSet or a custom init-method).
boolean	requiresDestruction(java.lang.Object bean) Determine whether the given bean instance requires destruction by this post-processor.
void	setServletConfig(ServletConfig servletConfig) Set the ServletConfig that this object runs in.
void	setServletContext(ServletContext servletContext) Set the ServletContext that this object runs in.
void	setUseSharedServletConfig(boolean useSharedServletConfig) Set whether to use the shared ServletConfig object passed in through setServletConfig, if available.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

SimpleServletPostProcessor

public SimpleServletPostProcessor()

Method Detail

setUseSharedServletConfig

public void setUseSharedServletConfig(boolean useSharedServletConfig)

Set whether to use the shared ServletConfig object passed in through setServletConfig, if available.

Default is "true". Turn this setting to "false" to pass in a mock ServletConfig object with the bean name as servlet name, holding the current ServletContext.

See Also:

setServletConfig(javax.servlet.ServletConfig)

setServletContext

public void setServletContext(ServletContext servletContext)

Description copied from interface: ServletContextAware

Set the ServletContext that this object runs in.

Invoked after population of normal bean properties but before an init callback like InitializingBean's afterPropertiesSet or a custom init-method. Invoked after ApplicationContextAware's setApplicationContext.

Specified by:

setServletContext in interface ServletContextAware

Parameters:

servletContext - ServletContext object to be used by this object

See Also:

InitializingBean.afterPropertiesSet(), ApplicationContextAware.setApplicationContext(org.springframework.context.ApplicationContext)

setServletConfig

public void setServletConfig(ServletConfig servletConfig)

Description copied from interface: ServletConfigAware

Set the ServletConfig that this object runs in.

Invoked after population of normal bean properties but before an init callback like InitializingBean's afterPropertiesSet or a custom init-method. Invoked after ApplicationContextAware's setApplicationContext.

Specified by:

setServletConfig in interface ServletConfigAware

Parameters:

servletConfig - ServletConfig object to be used by this object

See Also:

InitializingBean.afterPropertiesSet(), ApplicationContextAware.setApplicationContext(org.springframework.context.ApplicationContext)

postProcessBeforeInitialization

public java.lang.Object postProcessBeforeInitialization(java.lang.Object bean,
                                                        java.lang.String beanName)
                                                 throws BeansException

Description copied from interface: BeanPostProcessor

Apply this BeanPostProcessor to the given new bean instance before any bean initialization callbacks (like InitializingBean's afterPropertiesSet or a custom init-method). The bean will already be populated with property values. The returned bean instance may be a wrapper around the original.

The default implementation returns the given bean as-is.

Specified by:

postProcessBeforeInitialization in interface BeanPostProcessor

Parameters:

bean - the new bean instance

beanName - the name of the bean

Returns:

the bean instance to use, either the original or a wrapped one; if null, no subsequent BeanPostProcessors will be invoked

Throws:

BeansException - in case of errors

See Also:

InitializingBean.afterPropertiesSet()

postProcessAfterInitialization

public java.lang.Object postProcessAfterInitialization(java.lang.Object bean,
                                                       java.lang.String beanName)
                                                throws BeansException

Description copied from interface: BeanPostProcessor

Apply this BeanPostProcessor to the given new bean instance after any bean initialization callbacks (like InitializingBean's afterPropertiesSet or a custom init-method). The bean will already be populated with property values. The returned bean instance may be a wrapper around the original.

In case of a FactoryBean, this callback will be invoked for both the FactoryBean instance and the objects created by the FactoryBean (as of Spring 2.0). The post-processor can decide whether to apply to either the FactoryBean or created objects or both through corresponding bean instanceof FactoryBean checks.

This callback will also be invoked after a short-circuiting triggered by a InstantiationAwareBeanPostProcessor.postProcessBeforeInstantiation(java.lang.Class<?>, java.lang.String) method, in contrast to all other BeanPostProcessor callbacks.

The default implementation returns the given bean as-is.

Specified by:

postProcessAfterInitialization in interface BeanPostProcessor

Parameters:

bean - the new bean instance

beanName - the name of the bean

Returns:

the bean instance to use, either the original or a wrapped one; if null, no subsequent BeanPostProcessors will be invoked

Throws:

BeansException - in case of errors

See Also:

InitializingBean.afterPropertiesSet(), FactoryBean

postProcessBeforeDestruction

public void postProcessBeforeDestruction(java.lang.Object bean,
                                         java.lang.String beanName)
                                  throws BeansException

Description copied from interface: DestructionAwareBeanPostProcessor

Apply this BeanPostProcessor to the given bean instance before its destruction. Can invoke custom destruction callbacks.

Like DisposableBean's destroy and a custom destroy method, this callback just applies to singleton beans in the factory (including inner beans).

Specified by:

postProcessBeforeDestruction in interface DestructionAwareBeanPostProcessor

Parameters:

bean - the bean instance to be destroyed

beanName - the name of the bean

Throws:

BeansException - in case of errors

See Also:

DisposableBean, AbstractBeanDefinition.setDestroyMethodName(java.lang.String)

requiresDestruction

public boolean requiresDestruction(java.lang.Object bean)

Description copied from interface: DestructionAwareBeanPostProcessor

Determine whether the given bean instance requires destruction by this post-processor.

NOTE: Even as a late addition, this method has been introduced on DestructionAwareBeanPostProcessor itself instead of on a SmartDABPP subinterface. This allows existing DestructionAwareBeanPostProcessor implementations to easily provide requiresDestruction logic while retaining compatibility with Spring <4.3, and it is also an easier onramp to declaring requiresDestruction as a Java 8 default method in Spring 5.

If an implementation of DestructionAwareBeanPostProcessor does not provide a concrete implementation of this method, Spring's invocation mechanism silently assumes a method returning true (the effective default before 4.3, and the to-be-default in the Java 8 method in Spring 5).

Specified by:

requiresDestruction in interface DestructionAwareBeanPostProcessor

Parameters:

bean - the bean instance to check

Returns:

true if DestructionAwareBeanPostProcessor.postProcessBeforeDestruction(java.lang.Object, java.lang.String) is supposed to be called for this bean instance eventually, or false if not needed