org.apache.lucene.search
Enum CachingWrapperFilter.DeletesMode

java.lang.Object
  extended by java.lang.Enum<CachingWrapperFilter.DeletesMode>
      extended by org.apache.lucene.search.CachingWrapperFilter.DeletesMode
All Implemented Interfaces:
Serializable, Comparable<CachingWrapperFilter.DeletesMode>
Enclosing class:
CachingWrapperFilter

public static enum CachingWrapperFilter.DeletesMode
extends Enum<CachingWrapperFilter.DeletesMode>

Expert: Specifies how new deletions against a reopened reader should be handled.

The default is IGNORE, which means the cache entry will be re-used for a given segment, even when that segment has been reopened due to changes in deletions. This is a big performance gain, especially with near-real-timer readers, since you don't hit a cache miss on every reopened reader for prior segments.

However, in some cases this can cause invalid query results, allowing deleted documents to be returned. This only happens if the main query does not rule out deleted documents on its own, such as a toplevel ConstantScoreQuery. To fix this, use RECACHE to re-create the cached filter (at a higher per-reopen cost, but at faster subsequent search performance), or use DYNAMIC to dynamically intersect deleted docs (fast reopen time but some hit to search performance).


Enum Constant Summary
DYNAMIC
           
IGNORE
           
RECACHE
           
 
Method Summary
static CachingWrapperFilter.DeletesMode valueOf(String name)
          Returns the enum constant of this type with the specified name.
static CachingWrapperFilter.DeletesMode[] values()
          Returns an array containing the constants of this enum type, in the order they are declared.
 
Methods inherited from class java.lang.Enum
clone, compareTo, equals, finalize, getDeclaringClass, hashCode, name, ordinal, toString, valueOf
 
Methods inherited from class java.lang.Object
getClass, notify, notifyAll, wait, wait, wait
 

Enum Constant Detail

IGNORE

public static final CachingWrapperFilter.DeletesMode IGNORE

RECACHE

public static final CachingWrapperFilter.DeletesMode RECACHE

DYNAMIC

public static final CachingWrapperFilter.DeletesMode DYNAMIC
Method Detail

values

public static CachingWrapperFilter.DeletesMode[] values()
Returns an array containing the constants of this enum type, in the order they are declared. This method may be used to iterate over the constants as follows:
for (CachingWrapperFilter.DeletesMode c : CachingWrapperFilter.DeletesMode.values())
    System.out.println(c);

Returns:
an array containing the constants of this enum type, in the order they are declared

valueOf

public static CachingWrapperFilter.DeletesMode valueOf(String name)
Returns the enum constant of this type with the specified name. The string must match exactly an identifier used to declare an enum constant in this type. (Extraneous whitespace characters are not permitted.)

Parameters:
name - the name of the enum constant to be returned.
Returns:
the enum constant with the specified name
Throws:
IllegalArgumentException - if this enum type has no constant with the specified name
NullPointerException - if the argument is null


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