## org.springframework.context.support
Class ApplicationObjectSupport

    java.lang.Object
      org.springframework.context.support.ApplicationObjectSupport

All Implemented Interfaces:
  ApplicationContextAware

Direct Known Subclasses:
  AbstractHandlerMapping, PortletApplicationObjectSupport, WebApplicationObjectSupport

    public abstract class ApplicationObjectSupport

extends Object
implements ApplicationContextAware

Convenient superclass for application objects that want to be aware of the application context, e.g. for custom lookup of collaborating beans or for context-specific resource access. It saves the application context reference and provides an initialization callback method. Furthermore, it offers numerous convenience methods for message lookup.

There is no requirement to subclass this class: It just makes things a little easier if you need access to the context, e.g. for access to file resources or to the message source. Note that many application objects do not need to be aware of the application context at all, as they can receive collaborating beans via bean references.

Many framework classes are derived from this class, particularly within the web support.

Author:
  Rod Johnson, Juergen Hoeller
See Also:
  `WebApplicationObjectSupport`

Field Summary
`protected Log` `logger` Logger that is available to subclasses

Constructor Summary
`ApplicationObjectSupport()`

Method Summary
`ApplicationContext` `getApplicationContext()` Return the ApplicationContext that this object is associated with.
`protected MessageSourceAccessor` `getMessageSourceAccessor()` Return a MessageSourceAccessor for the application context used by this object, for easy message access.
`protected void` `initApplicationContext()` Subclasses can override this for custom initialization behavior.
`protected void` `initApplicationContext(ApplicationContext context)` Subclasses can override this for custom initialization behavior.
`protected boolean` `isContextRequired()` Determine whether this application object needs to run in an ApplicationContext.
`protected Class` `requiredContextClass()` Determine the context class that any context passed to `setApplicationContext` must be an instance of.
`void` `setApplicationContext(ApplicationContext context)` Set the ApplicationContext that this object runs in.

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### logger

    protected final Log logger

  Logger that is available to subclasses

Constructor Detail

### ApplicationObjectSupport

    public ApplicationObjectSupport()

Method Detail

### setApplicationContext

    public final void setApplicationContext(ApplicationContext context)
                                     throws BeansException

  Description copied from interface: `ApplicationContextAware`
  Set the ApplicationContext that this object runs in. Normally this call will be used to initialize the object.

  Invoked after population of normal bean properties but before an init callback such as `InitializingBean.afterPropertiesSet()` or a custom init-method. Invoked after `ResourceLoaderAware.setResourceLoader(org.springframework.core.io.ResourceLoader)`, `ApplicationEventPublisherAware.setApplicationEventPublisher(org.springframework.context.ApplicationEventPublisher)` and `MessageSourceAware`, if applicable.

  Specified by:
    `setApplicationContext` in interface `ApplicationContextAware`
  Parameters:
    `context` - the ApplicationContext object to be used by this object
  Throws:
    `ApplicationContextException` - in case of context initialization errors
    `BeansException` - if thrown by application context methods
  See Also:
    `BeanInitializationException`

### isContextRequired

    protected boolean isContextRequired()

  Determine whether this application object needs to run in an ApplicationContext.

  Default is "false". Can be overridden to enforce running in a context (i.e. to throw IllegalStateException on accessors if outside a context).

  See Also:
    `getApplicationContext()`, `getMessageSourceAccessor()`

### requiredContextClass

    protected Class requiredContextClass()

  Determine the context class that any context passed to `setApplicationContext` must be an instance of. Can be overridden in subclasses.

  See Also:
    `setApplicationContext(org.springframework.context.ApplicationContext)`

### initApplicationContext

    protected void initApplicationContext(ApplicationContext context)
                                   throws BeansException

  Subclasses can override this for custom initialization behavior. Gets called by `setApplicationContext` after setting the context instance.

  Note: Does not get called on reinitialization of the context but rather just on first initialization of this object's context reference.

  The default implementation calls the overloaded `initApplicationContext()` method without ApplicationContext reference.

  Parameters:
    `context` - the containing ApplicationContext
  Throws:
    `ApplicationContextException` - in case of initialization errors
    `BeansException` - if thrown by ApplicationContext methods
  See Also:
    `setApplicationContext(org.springframework.context.ApplicationContext)`

### initApplicationContext

    protected void initApplicationContext()
                                   throws BeansException

  Subclasses can override this for custom initialization behavior.

  The default implementation is empty. Called by `initApplicationContext(org.springframework.context.ApplicationContext)`.

  Throws:
    `ApplicationContextException` - in case of initialization errors
    `BeansException` - if thrown by ApplicationContext methods
  See Also:
    `setApplicationContext(org.springframework.context.ApplicationContext)`

### getApplicationContext

    public final ApplicationContext getApplicationContext()
                                                   throws IllegalStateException

  Return the ApplicationContext that this object is associated with.

  Throws:
    `IllegalStateException` - if not running in an ApplicationContext

### getMessageSourceAccessor

    protected final MessageSourceAccessor getMessageSourceAccessor()
                                                            throws IllegalStateException

  Return a MessageSourceAccessor for the application context used by this object, for easy message access.

  Throws:
    `IllegalStateException` - if not running in an ApplicationContext