org.apache.directory.server.core.api.normalization

Class FilterNormalizingVisitor

java.lang.Object

org.apache.directory.server.core.api.normalization.FilterNormalizingVisitor

All Implemented Interfaces:

org.apache.directory.api.ldap.model.filter.FilterVisitor

public class FilterNormalizingVisitor
extends java.lang.Object
implements org.apache.directory.api.ldap.model.filter.FilterVisitor

A filter visitor which normalizes leaf node values as it visits them. It also removes leaf nodes from branches whose attributeType is undefined. It obviously cannot remove a leaf node from a filter which is only a leaf node. Checks to see if a filter is a leaf node with undefined attributeTypes should be done outside this visitor. Since this visitor may remove filter nodes it may produce negative results on filters, like NOT branch nodes without a child or AND and OR nodes with one or less children. This might make some partition implementations choke. To avoid this problem we clean up branch nodes that don't make sense. For example all BranchNodes without children are just removed. An AND and OR BranchNode with a single child is replaced with it's child for all but the topmost branch node which we cannot replace. So again the top most branch node must be inspected by code outside of this visitor.

Field Summary

Fields

Modifier and Type	Field and Description
private static boolean[]	FILTER_CHAR Chars which need to be escaped in a filter '\0' | '(' | ')' | '*' | '\'
private static org.slf4j.Logger	LOG logger used by this class
private org.apache.directory.api.ldap.model.schema.normalizers.NameComponentNormalizer	ncn the name component normalizer used by this visitor
private org.apache.directory.api.ldap.model.schema.SchemaManager	schemaManager the SchemaManager instance used to resolve OIDs for attributeType ids

Constructor Summary

Constructors

Constructor and Description
FilterNormalizingVisitor(org.apache.directory.api.ldap.model.schema.normalizers.NameComponentNormalizer ncn, org.apache.directory.api.ldap.model.schema.SchemaManager schemaManager) Creates a new instance of NormalizingVisitor.

Method Summary

Modifier and Type	Method and Description
boolean	canVisit(org.apache.directory.api.ldap.model.filter.ExprNode node)
java.util.List<org.apache.directory.api.ldap.model.filter.ExprNode>	getOrder(org.apache.directory.api.ldap.model.filter.BranchNode node, java.util.List<org.apache.directory.api.ldap.model.filter.ExprNode> children)
static boolean	isFilterChar(char c) Check if the given char is a filter escaped char <filterEscapedChars> ::= '\0' | '(' | ')' | '*' | '\'
boolean	isPrefix()
private org.apache.directory.api.ldap.model.entry.Value<?>	normalizeValue(org.apache.directory.api.ldap.model.schema.AttributeType attributeType, org.apache.directory.api.ldap.model.entry.Value<?> value) A private method used to normalize a value.
java.lang.Object	visit(org.apache.directory.api.ldap.model.filter.ExprNode node) Visit the tree, normalizing the leaves and recusrsively visit the branches.
private org.apache.directory.api.ldap.model.filter.ExprNode	visitBranchNode(org.apache.directory.api.ldap.model.filter.BranchNode node) Visit a BranchNode.
private org.apache.directory.api.ldap.model.filter.ExprNode	visitExtensibleNode(org.apache.directory.api.ldap.model.filter.ExtensibleNode node) Visit a ExtensibleNode.
private org.apache.directory.api.ldap.model.filter.ExprNode	visitPresenceNode(org.apache.directory.api.ldap.model.filter.PresenceNode node) Visit a PresenceNode.
private org.apache.directory.api.ldap.model.filter.ExprNode	visitSimpleNode(org.apache.directory.api.ldap.model.filter.SimpleNode node) Visit a SimpleNode.
private org.apache.directory.api.ldap.model.filter.ExprNode	visitSubstringNode(org.apache.directory.api.ldap.model.filter.SubstringNode node) Visit a SubstringNode.

Methods inherited from class java.lang.Object

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

Field Detail

LOG

private static final org.slf4j.Logger LOG

logger used by this class

ncn

private final org.apache.directory.api.ldap.model.schema.normalizers.NameComponentNormalizer ncn

the name component normalizer used by this visitor

schemaManager

private final org.apache.directory.api.ldap.model.schema.SchemaManager schemaManager

the SchemaManager instance used to resolve OIDs for attributeType ids

FILTER_CHAR

private static final boolean[] FILTER_CHAR

Chars which need to be escaped in a filter '\0' | '(' | ')' | '*' | '\'

Constructor Detail

FilterNormalizingVisitor

public FilterNormalizingVisitor(org.apache.directory.api.ldap.model.schema.normalizers.NameComponentNormalizer ncn,
                                org.apache.directory.api.ldap.model.schema.SchemaManager schemaManager)

Creates a new instance of NormalizingVisitor.

Parameters:

ncn - The name component normalizer to use

schemaManager - The schemaManager

Method Detail

isFilterChar

public static boolean isFilterChar(char c)

Check if the given char is a filter escaped char <filterEscapedChars> ::= '\0' | '(' | ')' | '*' | '\'

Parameters:

c - the char we want to test

Returns:

true if the char is a pair char only

normalizeValue

private org.apache.directory.api.ldap.model.entry.Value<?> normalizeValue(org.apache.directory.api.ldap.model.schema.AttributeType attributeType,
                                                                          org.apache.directory.api.ldap.model.entry.Value<?> value)

A private method used to normalize a value. At this point, the value is a Value, we have to translate it to a Value if its AttributeType is H-R. Then we have to normalize the value accordingly to the AttributeType Normalizer.

Parameters:

attribute - The attribute's ID

value - The value to normalize

Returns:

the normalized value

visitPresenceNode

private org.apache.directory.api.ldap.model.filter.ExprNode visitPresenceNode(org.apache.directory.api.ldap.model.filter.PresenceNode node)
                                                                       throws org.apache.directory.api.ldap.model.exception.LdapException

Visit a PresenceNode. If the attribute exists, the node is returned, otherwise null is returned.

Parameters:

node - the node to visit

Returns:

The visited node

Throws:

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

visitSimpleNode

private org.apache.directory.api.ldap.model.filter.ExprNode visitSimpleNode(org.apache.directory.api.ldap.model.filter.SimpleNode node)
                                                                     throws org.apache.directory.api.ldap.model.exception.LdapException

Visit a SimpleNode. If the attribute exists, the node is returned, otherwise null is returned. SimpleNodes are : - ApproximateNode - EqualityNode - GreaterEqNode - LesserEqNode

Parameters:

node - the node to visit

Returns:

the visited node

Throws:

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

visitSubstringNode

private org.apache.directory.api.ldap.model.filter.ExprNode visitSubstringNode(org.apache.directory.api.ldap.model.filter.SubstringNode node)
                                                                        throws org.apache.directory.api.ldap.model.exception.LdapException

Visit a SubstringNode. If the attribute exists, the node is returned, otherwise null is returned. Normalizing substring value is pretty complex. It's not currently implemented...

Parameters:

node - the node to visit

Returns:

the visited node

Throws:

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

visitExtensibleNode

private org.apache.directory.api.ldap.model.filter.ExprNode visitExtensibleNode(org.apache.directory.api.ldap.model.filter.ExtensibleNode node)
                                                                         throws org.apache.directory.api.ldap.model.exception.LdapException

Visit a ExtensibleNode. If the attribute exists, the node is returned, otherwise null is returned. TODO implement the logic for ExtensibleNode

Parameters:

node - the node to visit

Returns:

the visited node

Throws:

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

visitBranchNode

private org.apache.directory.api.ldap.model.filter.ExprNode visitBranchNode(org.apache.directory.api.ldap.model.filter.BranchNode node)

Visit a BranchNode. BranchNodes are : - AndNode - NotNode - OrNode

Parameters:

node - the node to visit

Returns:

the visited node

visit

public java.lang.Object visit(org.apache.directory.api.ldap.model.filter.ExprNode node)

Visit the tree, normalizing the leaves and recusrsively visit the branches. Here are the leaves we are visiting : - PresenceNode ( attr =* ) - ExtensibleNode ( ? ) - SubStringNode ( attr = *X*Y* ) - ApproximateNode ( attr ~= value ) - EqualityNode ( attr = value ) - GreaterEqNode ( attr >= value ) - LessEqNode ( attr <= value ) The PresencNode is managed differently from other nodes, as it just check for the attribute, not the value.

Specified by:

visit in interface org.apache.directory.api.ldap.model.filter.FilterVisitor

Parameters:

node - the node to visit

Returns:

the visited node

canVisit

public boolean canVisit(org.apache.directory.api.ldap.model.filter.ExprNode node)

Specified by:

canVisit in interface org.apache.directory.api.ldap.model.filter.FilterVisitor

isPrefix

public boolean isPrefix()

Specified by:

isPrefix in interface org.apache.directory.api.ldap.model.filter.FilterVisitor

getOrder

public java.util.List<org.apache.directory.api.ldap.model.filter.ExprNode> getOrder(org.apache.directory.api.ldap.model.filter.BranchNode node,
                                                                                    java.util.List<org.apache.directory.api.ldap.model.filter.ExprNode> children)

Specified by:

getOrder in interface org.apache.directory.api.ldap.model.filter.FilterVisitor