| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, |
| * software distributed under the License is distributed on an |
| * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY |
| * KIND, either express or implied. See the License for the |
| * specific language governing permissions and limitations |
| * under the License. |
| * |
| */ |
| package org.apache.directory.server.xdbm.search.evaluator; |
| |
| |
| import org.apache.directory.api.ldap.model.entry.Entry; |
| import org.apache.directory.api.ldap.model.exception.LdapException; |
| import org.apache.directory.api.ldap.model.filter.ScopeNode; |
| import org.apache.directory.api.ldap.model.message.SearchScope; |
| import org.apache.directory.server.i18n.I18n; |
| import org.apache.directory.server.xdbm.IndexEntry; |
| import org.apache.directory.server.xdbm.ParentIdAndRdn; |
| import org.apache.directory.server.xdbm.Store; |
| import org.apache.directory.server.xdbm.search.Evaluator; |
| |
| |
| /** |
| * Evaluates one level scope assertions on candidates using an entry database. |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class OneLevelScopeEvaluator<E> implements Evaluator<ScopeNode> |
| { |
| /** The ScopeNode containing initial search scope constraints */ |
| private final ScopeNode node; |
| |
| /** The entry identifier of the scope base */ |
| private final String baseId; |
| |
| /** True if the scope requires alias dereferencing while searching */ |
| private final boolean dereferencing; |
| |
| /** the entry db storing entries */ |
| private final Store db; |
| |
| |
| /** |
| * Creates a one level scope node Evaluator for search expressions. |
| * |
| * @param node the scope node |
| * @param db the database used to evaluate scope node |
| * @throws Exception on db access failure |
| */ |
| public OneLevelScopeEvaluator( Store db, ScopeNode node ) throws Exception |
| { |
| this.node = node; |
| |
| if ( node.getScope() != SearchScope.ONELEVEL ) |
| { |
| throw new IllegalStateException( I18n.err( I18n.ERR_720 ) ); |
| } |
| |
| this.db = db; |
| baseId = node.getBaseId(); |
| dereferencing = node.getDerefAliases().isDerefInSearching() || node.getDerefAliases().isDerefAlways(); |
| } |
| |
| |
| /** |
| * Asserts whether or not a candidate has one level scope while taking |
| * alias dereferencing into account. |
| * |
| * TODO - terribly inefficient - would benefit from exposing the id of an |
| * entry within the Entry |
| * |
| * {@inheritDoc} |
| */ |
| public boolean evaluate( Entry candidate ) throws Exception |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_721 ) ); |
| } |
| |
| |
| /** |
| * Asserts whether or not a candidate has one level scope while taking |
| * alias dereferencing into account. |
| * |
| * @param candidate the candidate to assert |
| * @return true if the candidate is within one level scope |
| * @throws Exception if db lookups fail |
| * @see org.apache.directory.server.xdbm.search.Evaluator#evaluate(IndexEntry) |
| */ |
| public boolean evaluate( IndexEntry<?, String> indexEntry ) throws LdapException |
| { |
| ParentIdAndRdn parent = db.getRdnIndex().reverseLookup( indexEntry.getId() ); |
| boolean isChild = parent.getParentId().equals( baseId ); |
| Entry entry = indexEntry.getEntry(); |
| |
| // Fetch the entry |
| if ( null == entry ) |
| { |
| entry = db.fetch( indexEntry.getId() ); |
| |
| if ( null == entry ) |
| { |
| // The entry is not anymore present : get out |
| return false; |
| } |
| |
| indexEntry.setEntry( entry ); |
| } |
| |
| /* |
| * The candidate id could be any entry in the db. If search |
| * dereferencing is not enabled then we return the results of the child |
| * test. |
| */ |
| if ( !dereferencing ) |
| { |
| return isChild; |
| } |
| |
| /* |
| * From here down alias dereferencing is enabled. We determine if the |
| * candidate id is an alias, if so we reject it since aliases should |
| * not be returned. |
| */ |
| if ( null != db.getAliasIndex().reverseLookup( indexEntry.getId() ) ) |
| { |
| return false; |
| } |
| |
| /* |
| * The candidate is NOT an alias at this point. So if it is a child we |
| * just return true since it is in normal one level scope. |
| */ |
| if ( isChild ) |
| { |
| return true; |
| } |
| |
| /* |
| * At this point the candidate is not a child and it is not an alias. |
| * We need to check if the candidate is in extended one level scope by |
| * performing a lookup on the one level alias index. This index stores |
| * a tuple mapping the baseId to the id of objects brought into the |
| * one level scope of the base by an alias: ( baseId, aliasedObjId ) |
| * If the candidate id is an object brought into one level scope then |
| * the lookup returns true accepting the candidate. Otherwise the |
| * candidate is rejected with a false return because it is not in scope. |
| */ |
| return db.getOneAliasIndex().forward( baseId, indexEntry.getId() ); |
| } |
| |
| |
| public ScopeNode getExpression() |
| { |
| return node; |
| } |
| |
| |
| /** |
| * Gets the id of the search base associated with the ScopeNode expression. |
| * |
| * @return identifier of the search base |
| */ |
| public String getBaseId() |
| { |
| return baseId; |
| } |
| |
| |
| /** |
| * Gets whether or not dereferencing is enabled for this evaluator. |
| * |
| * @return true if dereferencing is enabled, false otherwise |
| */ |
| public boolean isDereferencing() |
| { |
| return dereferencing; |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString( String tabs ) |
| { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append( tabs ).append( "OneLevelScopEvaluator : " ).append( node ).append( "\n" ); |
| |
| return sb.toString(); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString() |
| { |
| return toString( "" ); |
| } |
| } |