org.apache.lucene.util

Class FieldCacheSanityChecker

java.lang.Object

org.apache.lucene.util.FieldCacheSanityChecker

public final class FieldCacheSanityChecker
extends Object

Provides methods for sanity checking that entries in the FieldCache are not wasteful or inconsistent.

Lucene 2.9 Introduced numerous enhancements into how the FieldCache is used by the low levels of Lucene searching (for Sorting and ValueSourceQueries) to improve both the speed for Sorting, as well as reopening of IndexReaders. But these changes have shifted the usage of FieldCache from "top level" IndexReaders (frequently a MultiReader or DirectoryReader) down to the leaf level SegmentReaders. As a result, existing applications that directly access the FieldCache may find RAM usage increase significantly when upgrading to 2.9 or Later. This class provides an API for these applications (or their Unit tests) to check at run time if the FieldCache contains "insane" usages of the FieldCache.

See Also:

FieldCache, FieldCacheSanityChecker.Insanity, FieldCacheSanityChecker.InsanityType

WARNING: This API is experimental and might change in incompatible ways in the next release.

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	FieldCacheSanityChecker.Insanity Simple container for a collection of related CacheEntry objects that in conjunction with each other represent some "insane" usage of the FieldCache.
static class	FieldCacheSanityChecker.InsanityType An Enumeration of the different types of "insane" behavior that may be detected in a FieldCache.

Constructor Summary

Constructors

Constructor and Description
FieldCacheSanityChecker()

Method Summary

Methods

Modifier and Type	Method and Description
FieldCacheSanityChecker.Insanity[]	check(FieldCache.CacheEntry... cacheEntries) Tests a CacheEntry[] for indication of "insane" cache usage.
static FieldCacheSanityChecker.Insanity[]	checkSanity(FieldCache.CacheEntry... cacheEntries) Quick and dirty convenience method that instantiates an instance with "good defaults" and uses it to test the CacheEntrys
static FieldCacheSanityChecker.Insanity[]	checkSanity(FieldCache cache) Quick and dirty convenience method
void	setRamUsageEstimator(boolean flag) If set, estimate size for all CacheEntry objects will be calculateed.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

FieldCacheSanityChecker

public FieldCacheSanityChecker()

Method Detail

setRamUsageEstimator

public void setRamUsageEstimator(boolean flag)

If set, estimate size for all CacheEntry objects will be calculateed.

checkSanity

public static FieldCacheSanityChecker.Insanity[] checkSanity(FieldCache cache)

Quick and dirty convenience method

See Also:

check(org.apache.lucene.search.FieldCache.CacheEntry...)

checkSanity

public static FieldCacheSanityChecker.Insanity[] checkSanity(FieldCache.CacheEntry... cacheEntries)

Quick and dirty convenience method that instantiates an instance with "good defaults" and uses it to test the CacheEntrys

See Also:

check(org.apache.lucene.search.FieldCache.CacheEntry...)

check

public FieldCacheSanityChecker.Insanity[] check(FieldCache.CacheEntry... cacheEntries)

Tests a CacheEntry[] for indication of "insane" cache usage.

NOTE:FieldCache CreationPlaceholder objects are ignored. (:TODO: is this a bad idea? are we masking a real problem?)