Class ServletContextParameterFactoryBean
- java.lang.Object
- org.springframework.web.context.support.ServletContextParameterFactoryBean
- All Implemented Interfaces:
Aware,FactoryBean<String>,ServletContextAware
public class ServletContextParameterFactoryBean extends Object implements FactoryBean<String>, ServletContextAware
FactoryBeanthat retrieves a specific ServletContext init parameter (that is, a "context-param" defined inweb.xml). Exposes that ServletContext init parameter when used as bean reference, effectively making it available as named Spring bean instance.NOTE: As of Spring 3.0, you may also use the "contextParameters" default bean which is of type Map, and dereference it using an "#{contextParameters.myKey}" expression to access a specific parameter by name.
- Since:
- 1.2.4
- Author:
- Juergen Hoeller
- See Also:
WebApplicationContext.CONTEXT_PARAMETERS_BEAN_NAME,ServletContextAttributeFactoryBean
Constructor Summary
Constructors Constructor Description ServletContextParameterFactoryBean()
Method Summary
All Methods Instance Methods Concrete Methods Modifier and Type Method Description StringgetObject()Return an instance (possibly shared or independent) of the object managed by this factory.Class<String>getObjectType()Return the type of object that this FactoryBean creates, ornullif not known in advance.booleanisSingleton()Is the object managed by this factory a singleton? That is, willFactoryBean.getObject()always return the same object (a reference that can be cached)?voidsetInitParamName(String initParamName)Set the name of the ServletContext init parameter to expose.voidsetServletContext(ServletContext servletContext)Set theServletContextthat this object runs in.
Constructor Detail
ServletContextParameterFactoryBean
public ServletContextParameterFactoryBean()
Method Detail
setInitParamName
public void setInitParamName(String initParamName)
Set the name of the ServletContext init parameter to expose.
setServletContext
public void setServletContext(ServletContext servletContext)
Description copied from interface:ServletContextAwareSet theServletContextthat this object runs in.Invoked after population of normal bean properties but before an init callback like InitializingBean's
afterPropertiesSetor a custom init-method. Invoked after ApplicationContextAware'ssetApplicationContext.- Specified by:
setServletContextin interfaceServletContextAware- Parameters:
servletContext- ServletContext object to be used by this object- See Also:
InitializingBean.afterPropertiesSet(),ApplicationContextAware.setApplicationContext(org.springframework.context.ApplicationContext)
getObject
public String getObject()
Description copied from interface:FactoryBeanReturn an instance (possibly shared or independent) of the object managed by this factory.As with a
BeanFactory, this allows support for both the Singleton and Prototype design pattern.If this FactoryBean is not fully initialized yet at the time of the call (for example because it is involved in a circular reference), throw a corresponding
FactoryBeanNotInitializedException.As of Spring 2.0, FactoryBeans are allowed to return
nullobjects. The factory will consider this as normal value to be used; it will not throw a FactoryBeanNotInitializedException in this case anymore. FactoryBean implementations are encouraged to throw FactoryBeanNotInitializedException themselves now, as appropriate.- Specified by:
getObjectin interfaceFactoryBean<String>- Returns:
- an instance of the bean (can be
null) - See Also:
FactoryBeanNotInitializedException
getObjectType
public Class<String> getObjectType()
Description copied from interface:FactoryBeanReturn the type of object that this FactoryBean creates, ornullif not known in advance.This allows one to check for specific types of beans without instantiating objects, for example on autowiring.
In the case of implementations that are creating a singleton object, this method should try to avoid singleton creation as far as possible; it should rather estimate the type in advance. For prototypes, returning a meaningful type here is advisable too.
This method can be called before this FactoryBean has been fully initialized. It must not rely on state created during initialization; of course, it can still use such state if available.
NOTE: Autowiring will simply ignore FactoryBeans that return
nullhere. Therefore it is highly recommended to implement this method properly, using the current state of the FactoryBean.- Specified by:
getObjectTypein interfaceFactoryBean<String>- Returns:
- the type of object that this FactoryBean creates, or
nullif not known at the time of the call - See Also:
ListableBeanFactory.getBeansOfType(java.lang.Class<T>)
isSingleton
public boolean isSingleton()
Description copied from interface:FactoryBeanIs the object managed by this factory a singleton? That is, willFactoryBean.getObject()always return the same object (a reference that can be cached)?NOTE: If a FactoryBean indicates to hold a singleton object, the object returned from
getObject()might get cached by the owning BeanFactory. Hence, do not returntrueunless the FactoryBean always exposes the same reference.The singleton status of the FactoryBean itself will generally be provided by the owning BeanFactory; usually, it has to be defined as singleton there.
NOTE: This method returning
falsedoes not necessarily indicate that returned objects are independent instances. An implementation of the extendedSmartFactoryBeaninterface may explicitly indicate independent instances through itsSmartFactoryBean.isPrototype()method. PlainFactoryBeanimplementations which do not implement this extended interface are simply assumed to always return independent instances if theisSingleton()implementation returnsfalse.- Specified by:
isSingletonin interfaceFactoryBean<String>- Returns:
- whether the exposed object is a singleton
- See Also:
FactoryBean.getObject(),SmartFactoryBean.isPrototype()