org.apache.directory.server.xdbm.search.evaluator

Class AndEvaluator

java.lang.Object

org.apache.directory.server.xdbm.search.evaluator.AndEvaluator

All Implemented Interfaces:

Evaluator<org.apache.directory.api.ldap.model.filter.AndNode>

public class AndEvaluator
extends java.lang.Object
implements Evaluator<org.apache.directory.api.ldap.model.filter.AndNode>

An Evaluator for logical conjunction (AND) expressions.

Field Summary

Fields

Modifier and Type	Field and Description
private java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>>	evaluators The list of evaluators associated with each of the children
private org.apache.directory.api.ldap.model.filter.AndNode	node The AndNode

Constructor Summary

Constructors

Constructor and Description
AndEvaluator(org.apache.directory.api.ldap.model.filter.AndNode node, java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>> evaluators) Creates an instance of AndEvaluator

Method Summary

Modifier and Type	Method and Description
private java.lang.String	dumpEvaluators(java.lang.String tabs) Dumps the evaluators
boolean	evaluate(org.apache.directory.api.ldap.model.entry.Entry entry) Evaluates whether or not a candidate, satisfies the expression associated with this Evaluator .
boolean	evaluate(IndexEntry<?,java.lang.String> indexEntry) Evaluates a candidate to determine if a filter expression selects it.
org.apache.directory.api.ldap.model.filter.AndNode	getExpression() Gets the expression used by this expression Evaluator.
private java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>>	optimize(java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>> unoptimized) Takes a set of Evaluators and copies then sorts them in a new list with increasing scan counts on their expression nodes.
java.lang.String	toString()
java.lang.String	toString(java.lang.String tabs) Pretty-print an Evaluator

Methods inherited from class java.lang.Object

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

Field Detail

evaluators

private final java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>> evaluators

The list of evaluators associated with each of the children

node

private final org.apache.directory.api.ldap.model.filter.AndNode node

The AndNode

Constructor Detail

AndEvaluator

public AndEvaluator(org.apache.directory.api.ldap.model.filter.AndNode node,
                    java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>> evaluators)

Creates an instance of AndEvaluator

Parameters:

node - The And Node

evaluators - The list of evaluators for all the contaned nodes

Method Detail

optimize

private java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>> optimize(java.util.List<Evaluator<? extends org.apache.directory.api.ldap.model.filter.ExprNode>> unoptimized)

Takes a set of Evaluators and copies then sorts them in a new list with increasing scan counts on their expression nodes. This is done to have the Evaluators with the least scan count which have the highest probability of rejecting a candidate first. That will increase the chance of shorting the checks on evaluators early so extra lookups and comparisons are avoided.

Parameters:

unoptimized - the unoptimized list of Evaluators

Returns:

optimized Evaluator list with increasing scan count ordering

evaluate

public boolean evaluate(org.apache.directory.api.ldap.model.entry.Entry entry)
                 throws java.lang.Exception

Evaluates whether or not a candidate, satisfies the expression associated with this Evaluator .

Specified by:

evaluate in interface Evaluator<org.apache.directory.api.ldap.model.filter.AndNode>

Parameters:

entry - the candidate entry

Returns:

true if filter selects the candidate false otherwise

Throws:

java.lang.Exception - if there are faults during evaluation

evaluate

public boolean evaluate(IndexEntry<?,java.lang.String> indexEntry)
                 throws org.apache.directory.api.ldap.model.exception.LdapException

Evaluates a candidate to determine if a filter expression selects it. If an IndexEntry does has a null reference to the entry object, this Evaluator may set it if it has to access the full entry within the master table of the store. Subsequent evaluations on the IndexEntry then need not access the store to retreive the entry if they need to access it's attributes.

Specified by:

evaluate in interface Evaluator<org.apache.directory.api.ldap.model.filter.AndNode>

Parameters:

indexEntry - the index record of the entry to evaluate

Returns:

true if filter selects the candidate false otherwise

Throws:

org.apache.directory.api.ldap.model.exception.LdapException

getExpression

public org.apache.directory.api.ldap.model.filter.AndNode getExpression()

Gets the expression used by this expression Evaluator.

Specified by:

getExpression in interface Evaluator<org.apache.directory.api.ldap.model.filter.AndNode>

Returns:

the AST for the expression

dumpEvaluators

private java.lang.String dumpEvaluators(java.lang.String tabs)

Dumps the evaluators

toString

public java.lang.String toString(java.lang.String tabs)

Description copied from interface: Evaluator

Pretty-print an Evaluator

Specified by:

toString in interface Evaluator<org.apache.directory.api.ldap.model.filter.AndNode>

Parameters:

tabs - The tabs to add before the evaluator

Returns:

The pretty-printed evaluator and its descendants

See Also:

Object.toString()

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

See Also:

Object.toString()