Interface ContextCache
- All Known Implementing Classes:
DefaultContextCache
ContextCache
defines the SPI for caching Spring
ApplicationContexts
within the
Spring TestContext Framework.
A ContextCache
maintains a cache of ApplicationContexts
keyed by MergedContextConfiguration
instances, potentially configured
with a maximum size and
a custom eviction policy.
As of Spring Framework 6.1, this SPI includes optional support for tracking and incrementing failure counts.
Rationale
Context caching can have significant performance benefits if context
initialization is complex. Although the initialization of a Spring context
itself is typically very quick, some beans in a context — for example,
an embedded database or a LocalContainerEntityManagerFactoryBean
for
working with JPA — may take several seconds to initialize. Hence, it
often makes sense to perform that initialization only once per test suite or
JVM process.
- Since:
- 4.2
- Author:
- Sam Brannen, Juergen Hoeller
- See Also:
-
Field Summary
Modifier and TypeFieldDescriptionstatic final String
The name of the logging category used for reportingContextCache
statistics.static final int
The default maximum size of the context cache: 32.static final String
System property used to configure the maximum size of theContextCache
as a positive integer: "spring.test.context.cache.maxSize". -
Method Summary
Modifier and TypeMethodDescriptionvoid
clear()
Clear all contexts from the cache, clearing context hierarchy information as well.void
Clear hit count and miss count statistics for the cache (i.e., reset counters to zero).boolean
Determine whether there is a cached context for the given key.Obtain a cachedApplicationContext
for the given key.default int
Get the failure count for the given key.int
Get the overall hit count for this cache.int
Get the overall miss count for this cache.int
Determine the number of parent contexts currently tracked within the cache.default void
Increment the failure count for the given key.void
Log the statistics for thisContextCache
atDEBUG
level using the "org.springframework.test.context.cache" logging category.void
put
(MergedContextConfiguration key, ApplicationContext context) Explicitly add anApplicationContext
instance to the cache under the given key, potentially honoring a custom eviction policy.void
remove
(MergedContextConfiguration key, DirtiesContext.HierarchyMode hierarchyMode) Remove the context with the given key from the cache and explicitly close it if it is an instance ofConfigurableApplicationContext
.void
reset()
Reset all state maintained by this cache including statistics.int
size()
Determine the number of contexts currently stored in the cache.
-
Field Details
-
CONTEXT_CACHE_LOGGING_CATEGORY
The name of the logging category used for reportingContextCache
statistics.- See Also:
-
DEFAULT_MAX_CONTEXT_CACHE_SIZE
static final int DEFAULT_MAX_CONTEXT_CACHE_SIZEThe default maximum size of the context cache: 32.- Since:
- 4.3
- See Also:
-
MAX_CONTEXT_CACHE_SIZE_PROPERTY_NAME
System property used to configure the maximum size of theContextCache
as a positive integer: "spring.test.context.cache.maxSize".May alternatively be configured via the
SpringProperties
mechanism.Note that implementations of
ContextCache
are not required to actually support a maximum cache size. Consult the documentation of the corresponding implementation for details.- Since:
- 4.3
- See Also:
-
-
Method Details
-
contains
Determine whether there is a cached context for the given key.- Parameters:
key
- the context key (nevernull
)- Returns:
true
if the cache contains a context with the given key
-
get
Obtain a cachedApplicationContext
for the given key.- Parameters:
key
- the context key (nevernull
)- Returns:
- the corresponding
ApplicationContext
instance, ornull
if not found in the cache - See Also:
-
put
Explicitly add anApplicationContext
instance to the cache under the given key, potentially honoring a custom eviction policy.- Parameters:
key
- the context key (nevernull
)context
- theApplicationContext
instance (nevernull
)
-
remove
Remove the context with the given key from the cache and explicitly close it if it is an instance ofConfigurableApplicationContext
.Generally speaking, this method should be called to properly evict a context from the cache (for example, due to a custom eviction policy) or if the state of a singleton bean has been modified, potentially affecting future interaction with the context.
In addition, the semantics of the supplied
HierarchyMode
must be honored. See the Javadoc forDirtiesContext.HierarchyMode
for details.- Parameters:
key
- the context key; nevernull
hierarchyMode
- the hierarchy mode; may benull
if the context is not part of a hierarchy
-
getFailureCount
Get the failure count for the given key.A failure is any attempt to load the
ApplicationContext
for the given key that results in an exception.The default implementation of this method always returns
0
. Concrete implementations are therefore highly encouraged to override this method andincrementFailureCount(MergedContextConfiguration)
with appropriate behavior. Note that the standardContextContext
implementation in Spring overrides these methods appropriately.- Parameters:
key
- the context key; nevernull
- Since:
- 6.1
- See Also:
-
incrementFailureCount
Increment the failure count for the given key.The default implementation of this method does nothing. Concrete implementations are therefore highly encouraged to override this method and
getFailureCount(MergedContextConfiguration)
with appropriate behavior. Note that the standardContextContext
implementation in Spring overrides these methods appropriately.- Parameters:
key
- the context key; nevernull
- Since:
- 6.1
- See Also:
-
size
int size()Determine the number of contexts currently stored in the cache.If the cache contains more than
Integer.MAX_VALUE
elements, this method must returnInteger.MAX_VALUE
. -
getParentContextCount
int getParentContextCount()Determine the number of parent contexts currently tracked within the cache. -
getHitCount
int getHitCount()Get the overall hit count for this cache.A hit is any access to the cache that returns a non-null context for the queried key.
-
getMissCount
int getMissCount()Get the overall miss count for this cache.A miss is any access to the cache that returns a
null
context for the queried key. -
reset
void reset()Reset all state maintained by this cache including statistics.- See Also:
-
clear
void clear()Clear all contexts from the cache, clearing context hierarchy information as well. -
clearStatistics
void clearStatistics()Clear hit count and miss count statistics for the cache (i.e., reset counters to zero). -
logStatistics
void logStatistics()Log the statistics for thisContextCache
atDEBUG
level using the "org.springframework.test.context.cache" logging category.The following information should be logged.
- name of the concrete
ContextCache
implementation - size()
- parent context count
- hit count
- miss count
- any other information useful for monitoring the state of this cache
- name of the concrete
-