类 AbstractCachingViewResolver
- java.lang.Object
- org.springframework.context.support.ApplicationObjectSupport
- org.springframework.web.context.support.WebApplicationObjectSupport
- org.springframework.web.servlet.view.AbstractCachingViewResolver
- 所有已实现的接口:
Aware
,ApplicationContextAware
,ServletContextAware
,ViewResolver
public abstract class AbstractCachingViewResolver extends WebApplicationObjectSupport implements ViewResolver
Convenient base class forViewResolver
implementations. CachesView
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(java.lang.String, java.util.Locale)
template method, building the View object for a specific view name and locale.- 作者:
- Rod Johnson, Juergen Hoeller
- 另请参阅:
loadView(java.lang.String, java.util.Locale)
字段概要
字段 修饰符和类型 字段 说明 static int
DEFAULT_CACHE_LIMIT
Default maximum number of entries for the view cache: 1024从类继承的字段 org.springframework.context.support.ApplicationObjectSupport
logger
构造器概要
构造器 构造器 说明 AbstractCachingViewResolver()
方法概要
所有方法 实例方法 抽象方法 具体方法 修饰符和类型 方法 说明 void
clearCache()
Clear the entire view cache, removing all cached view objects.protected View
createView(String viewName, Locale locale)
Create the actual View object.protected Object
getCacheKey(String viewName, Locale locale)
Return the cache key for the given view name and the given locale.int
getCacheLimit()
Return the maximum number of entries for the view cache.boolean
isCache()
Return if caching is enabled.boolean
isCacheUnresolved()
Return if caching of unresolved views is enabled.protected abstract View
loadView(String viewName, Locale locale)
Subclasses must implement this method, building a View object for the specified view.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.void
setCacheLimit(int cacheLimit)
Specify the maximum number of entries for the view cache.void
setCacheUnresolved(boolean cacheUnresolved)
Whether a view name once resolved tonull
should be cached and automatically resolved tonull
subsequently.从类继承的方法 org.springframework.web.context.support.WebApplicationObjectSupport
getServletContext, getTempDir, getWebApplicationContext, initApplicationContext, initServletContext, isContextRequired, setServletContext
从类继承的方法 org.springframework.context.support.ApplicationObjectSupport
getApplicationContext, getMessageSourceAccessor, initApplicationContext, requiredContextClass, setApplicationContext
字段详细资料
DEFAULT_CACHE_LIMIT
public static final int DEFAULT_CACHE_LIMIT
Default maximum number of entries for the view cache: 1024- 另请参阅:
- 常量字段值
构造器详细资料
AbstractCachingViewResolver
public AbstractCachingViewResolver()
方法详细资料
setCacheLimit
public void setCacheLimit(int cacheLimit)
Specify the maximum number of entries for the view cache. Default is 1024.
getCacheLimit
public int getCacheLimit()
Return the maximum number of entries for the view cache.
setCache
public void setCache(boolean cache)
Enable or disable caching.This is equivalent to setting the
"cacheLimit"
property to the default limit (1024) or to 0, respectively.Default is "true": caching is enabled. Disable this only for debugging and development.
isCache
public boolean isCache()
Return if caching is enabled.
setCacheUnresolved
public void setCacheUnresolved(boolean cacheUnresolved)
Whether a view name once resolved tonull
should be cached and automatically resolved tonull
subsequently.Default is "true": unresolved view names are being cached, as of Spring 3.1. Note that this flag only applies if the general
"cache"
flag is kept at its default of "true" as well.Of specific interest is the ability for some AbstractUrlBasedView implementations (FreeMarker, Velocity, Tiles) to check if an underlying resource exists via
AbstractUrlBasedView.checkResource(Locale)
. With this flag set to "false", an underlying resource that re-appears is noticed and used. With the flag set to "true", one check is made only.
isCacheUnresolved
public boolean isCacheUnresolved()
Return if caching of unresolved views is enabled.
resolveViewName
public View resolveViewName(String viewName, Locale locale) throws Exception
从接口复制的说明:ViewResolver
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 returnnull
(rather throwing an exception when View creation failed).- 指定者:
resolveViewName
在接口中ViewResolver
- 参数:
viewName
- name of the view to resolvelocale
- Locale in which to resolve the view. ViewResolvers that support internationalization should respect this.- 返回:
- the View object, or
null
if not found (optional, to allow for ViewResolver chaining) - 抛出:
Exception
- if the view cannot be resolved (typically in case of problems creating an actual View object)
getCacheKey
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.
removeFromCache
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.
- 参数:
viewName
- the view name for which the cached view object (if any) needs to be removedlocale
- the locale for which the view object should be removed
clearCache
public void clearCache()
Clear the entire view cache, removing all cached view objects. Subsequent resolve calls will lead to recreation of demanded view objects.
createView
protected View createView(String viewName, Locale locale) throws Exception
Create the actual View object.The default implementation delegates to
loadView(java.lang.String, java.util.Locale)
. This can be overridden to resolve certain view names in a special fashion, before delegating to the actualloadView
implementation provided by the subclass.- 参数:
viewName
- the name of the view to retrievelocale
- the Locale to retrieve the view for- 返回:
- the View instance, or
null
if not found (optional, to allow for ViewResolver chaining) - 抛出:
Exception
- if the view couldn't be resolved- 另请参阅:
loadView(java.lang.String, java.util.Locale)
loadView
protected abstract View loadView(String viewName, Locale locale) throws Exception
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.
- 参数:
viewName
- the name of the view to retrievelocale
- the Locale to retrieve the view for- 返回:
- the View instance, or
null
if not found (optional, to allow for ViewResolver chaining) - 抛出:
Exception
- if the view couldn't be resolved- 另请参阅:
resolveViewName(java.lang.String, java.util.Locale)