public abstract class

AbstractCachingViewResolver

extends WebApplicationObjectSupport
implements ViewResolver
java.lang.Object
   ↳ org.springframework.context.support.ApplicationObjectSupport
     ↳ org.springframework.web.context.support.WebApplicationObjectSupport
       ↳ org.springframework.web.servlet.view.AbstractCachingViewResolver
Known Direct Subclasses
Known Indirect Subclasses

Class Overview

Convenient base class for ViewResolver implementations. Caches View objects once resolved: This means that view resolution won't be a performance problem, no matter how costly initial view retrieval is.

Subclasses need to implement the loadView(String, Locale) template method, building the View object for a specific view name and locale.

Summary

[Expand]
Inherited Fields
From class org.springframework.context.support.ApplicationObjectSupport
Public Constructors
AbstractCachingViewResolver()
Public Methods
void clearCache()
Clear the entire view cache, removing all cached view objects.
boolean isCache()
Return if caching is enabled.
void removeFromCache(String viewName, Locale locale)
Provides functionality to clear the cache for a certain view.
View resolveViewName(String viewName, Locale locale)
Resolve the given view by name.
void setCache(boolean cache)
Enable or disable caching.
Protected Methods
View createView(String viewName, Locale locale)
Create the actual View object.
Object getCacheKey(String viewName, Locale locale)
Return the cache key for the given view name and the given locale.
abstract View loadView(String viewName, Locale locale)
Subclasses must implement this method, building a View object for the specified view.
[Expand]
Inherited Methods
From class org.springframework.web.context.support.WebApplicationObjectSupport
From class org.springframework.context.support.ApplicationObjectSupport
From class java.lang.Object
From interface org.springframework.context.ApplicationContextAware
From interface org.springframework.web.context.ServletContextAware
From interface org.springframework.web.servlet.ViewResolver

Public Constructors

public AbstractCachingViewResolver ()

Public Methods

public void clearCache ()

Clear the entire view cache, removing all cached view objects. Subsequent resolve calls will lead to recreation of demanded view objects.

public boolean isCache ()

Return if caching is enabled.

public void removeFromCache (String viewName, Locale locale)

Provides functionality to clear the cache for a certain view.

This can be handy in case developer are able to modify views (e.g. Velocity templates) at runtime after which you'd need to clear the cache for the specified view.

Parameters
viewName the view name for which the cached view object (if any) needs to be removed
locale the locale for which the view object should be removed

public View resolveViewName (String viewName, Locale locale)

Resolve the given view by name.

Note: To allow for ViewResolver chaining, a ViewResolver should return null if a view with the given name is not defined in it. However, this is not required: Some ViewResolvers will always attempt to build View objects with the given name, unable to return null (rather throwing an exception when View creation failed).

Parameters
viewName name of the view to resolve
locale Locale in which to resolve the view. ViewResolvers that support internationalization should respect this.
Returns
  • the View object, or null if not found (optional, to allow for ViewResolver chaining)
Throws
Exception

public void setCache (boolean cache)

Enable or disable caching.

Default is "true": caching is enabled. Disable this only for debugging and development.

Warning: Disabling caching can severely impact performance.

Protected Methods

protected View createView (String viewName, Locale locale)

Create the actual View object.

The default implementation delegates to loadView(String, Locale). This can be overridden to resolve certain view names in a special fashion, before delegating to the actual loadView implementation provided by the subclass.

Parameters
viewName the name of the view to retrieve
locale the Locale to retrieve the view for
Returns
  • the View instance, or null if not found (optional, to allow for ViewResolver chaining)
Throws
Exception if the view couldn't be resolved

protected Object getCacheKey (String viewName, Locale locale)

Return the cache key for the given view name and the given locale.

Default is a String consisting of view name and locale suffix. Can be overridden in subclasses.

Needs to respect the locale in general, as a different locale can lead to a different view resource.

protected abstract View loadView (String viewName, Locale locale)

Subclasses must implement this method, building a View object for the specified view. The returned View objects will be cached by this ViewResolver base class.

Subclasses are not forced to support internationalization: A subclass that does not may simply ignore the locale parameter.

Parameters
viewName the name of the view to retrieve
locale the Locale to retrieve the view for
Returns
  • the View instance, or null if not found (optional, to allow for ViewResolver chaining)
Throws
Exception if the view couldn't be resolved