| /* |
| * 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.cursor; |
| |
| |
| import org.apache.directory.api.ldap.model.constants.Loggers; |
| import org.apache.directory.api.ldap.model.cursor.Cursor; |
| import org.apache.directory.api.ldap.model.cursor.CursorException; |
| import org.apache.directory.api.ldap.model.cursor.InvalidCursorPositionException; |
| import org.apache.directory.api.ldap.model.exception.LdapException; |
| import org.apache.directory.api.ldap.model.schema.AttributeType; |
| import org.apache.directory.server.i18n.I18n; |
| import org.apache.directory.server.xdbm.AbstractIndexCursor; |
| import org.apache.directory.server.xdbm.IndexEntry; |
| import org.apache.directory.server.xdbm.Store; |
| import org.apache.directory.server.xdbm.search.evaluator.PresenceEvaluator; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| |
| /** |
| * A returning candidates satisfying an attribute presence expression. |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class PresenceCursor extends AbstractIndexCursor<String> |
| { |
| /** A dedicated log for cursors */ |
| private static final Logger LOG_CURSOR = LoggerFactory.getLogger( Loggers.CURSOR_LOG.getName() ); |
| |
| /** Speedup for logs */ |
| private static final boolean IS_DEBUG = LOG_CURSOR.isDebugEnabled(); |
| |
| private static final String UNSUPPORTED_MSG = I18n.err( I18n.ERR_724 ); |
| private final Cursor<IndexEntry<String, String>> uuidCursor; |
| private final Cursor<IndexEntry<String, String>> presenceCursor; |
| private final PresenceEvaluator presenceEvaluator; |
| |
| /** The prefetched entry, if it's a valid one */ |
| private IndexEntry<String, String> prefetched; |
| |
| |
| public PresenceCursor( Store store, PresenceEvaluator presenceEvaluator ) throws Exception |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Creating PresenceCursor {}", this ); |
| } |
| |
| this.presenceEvaluator = presenceEvaluator; |
| AttributeType type = presenceEvaluator.getAttributeType(); |
| |
| // we don't maintain a presence index for objectClass, and entryCSN |
| // as it doesn't make sense because every entry has such an attribute |
| // instead for those attributes and all un-indexed attributes we use the ndn index |
| if ( store.hasUserIndexOn( type ) ) |
| { |
| presenceCursor = store.getPresenceIndex().forwardCursor( type.getOid() ); |
| uuidCursor = null; |
| } |
| else |
| { |
| presenceCursor = null; |
| uuidCursor = new AllEntriesCursor( store ); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| protected String getUnsupportedMessage() |
| { |
| return UNSUPPORTED_MSG; |
| } |
| |
| |
| public boolean available() |
| { |
| if ( presenceCursor != null ) |
| { |
| return presenceCursor.available(); |
| } |
| |
| return super.available(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void before( IndexEntry<String, String> element ) throws LdapException, CursorException |
| { |
| checkNotClosed( "before()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| presenceCursor.before( element ); |
| |
| return; |
| } |
| |
| super.before( element ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void after( IndexEntry<String, String> element ) throws LdapException, CursorException |
| { |
| checkNotClosed( "after()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| presenceCursor.after( element ); |
| |
| return; |
| } |
| |
| super.after( element ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void beforeFirst() throws LdapException, CursorException |
| { |
| checkNotClosed( "beforeFirst()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| presenceCursor.beforeFirst(); |
| |
| return; |
| } |
| |
| uuidCursor.beforeFirst(); |
| setAvailable( false ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void afterLast() throws LdapException, CursorException |
| { |
| checkNotClosed( "afterLast()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| presenceCursor.afterLast(); |
| return; |
| } |
| |
| uuidCursor.afterLast(); |
| setAvailable( false ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean first() throws LdapException, CursorException |
| { |
| checkNotClosed( "first()" ); |
| if ( presenceCursor != null ) |
| { |
| return presenceCursor.first(); |
| } |
| |
| beforeFirst(); |
| return next(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean last() throws LdapException, CursorException |
| { |
| checkNotClosed( "last()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| return presenceCursor.last(); |
| } |
| |
| afterLast(); |
| |
| return previous(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean previous() throws LdapException, CursorException |
| { |
| checkNotClosed( "previous()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| return presenceCursor.previous(); |
| } |
| |
| while ( uuidCursor.previous() ) |
| { |
| checkNotClosed( "previous()" ); |
| IndexEntry<?, String> candidate = uuidCursor.get(); |
| |
| if ( presenceEvaluator.evaluate( candidate ) ) |
| { |
| return setAvailable( true ); |
| } |
| } |
| |
| return setAvailable( false ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean next() throws LdapException, CursorException |
| { |
| checkNotClosed( "next()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| return presenceCursor.next(); |
| } |
| |
| while ( uuidCursor.next() ) |
| { |
| checkNotClosed( "next()" ); |
| IndexEntry<String, String> candidate = uuidCursor.get(); |
| |
| if ( presenceEvaluator.evaluate( candidate ) ) |
| { |
| prefetched = candidate; |
| |
| return setAvailable( true ); |
| } |
| } |
| |
| return setAvailable( false ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public IndexEntry<String, String> get() throws CursorException |
| { |
| checkNotClosed( "get()" ); |
| |
| if ( presenceCursor != null ) |
| { |
| if ( presenceCursor.available() ) |
| { |
| return presenceCursor.get(); |
| } |
| |
| throw new InvalidCursorPositionException( I18n.err( I18n.ERR_708 ) ); |
| } |
| |
| if ( available() ) |
| { |
| if ( prefetched == null ) |
| { |
| prefetched = uuidCursor.get(); |
| } |
| |
| /* |
| * The value of NDN indices is the normalized dn and we want the |
| * value to be the value of the attribute in question. So we will |
| * set that accordingly here. |
| */ |
| prefetched.setKey( presenceEvaluator.getAttributeType().getOid() ); |
| |
| return prefetched; |
| } |
| |
| throw new InvalidCursorPositionException( I18n.err( I18n.ERR_708 ) ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void close() |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Closing PresenceCursor {}", this ); |
| } |
| |
| super.close(); |
| |
| if ( presenceCursor != null ) |
| { |
| presenceCursor.close(); |
| } |
| else |
| { |
| uuidCursor.close(); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void close( Exception cause ) |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Closing PresenceCursor {}", this ); |
| } |
| |
| super.close( cause ); |
| |
| if ( presenceCursor != null ) |
| { |
| presenceCursor.close( cause ); |
| } |
| else |
| { |
| uuidCursor.close( cause ); |
| } |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString( String tabs ) |
| { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append( tabs ).append( "PresenceCursor (" ); |
| |
| if ( available() ) |
| { |
| sb.append( "available)" ); |
| } |
| else |
| { |
| sb.append( "absent)" ); |
| } |
| |
| sb.append( " :\n" ); |
| |
| sb.append( tabs + " >>" ).append( presenceEvaluator ).append( '\n' ); |
| |
| if ( presenceCursor != null ) |
| { |
| sb.append( tabs + " <presence>\n" ); |
| sb.append( presenceCursor.toString( tabs + " " ) ); |
| } |
| |
| if ( uuidCursor != null ) |
| { |
| sb.append( tabs + " <uuid>\n" ); |
| sb.append( uuidCursor.toString( tabs + " " ) ); |
| } |
| |
| return sb.toString(); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString() |
| { |
| return toString( "" ); |
| } |
| } |