| /* |
| * 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.exception.LdapException; |
| 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.ParentIdAndRdn; |
| import org.apache.directory.server.xdbm.Store; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| |
| /** |
| * A Cursor over entries satisfying one level scope constraints with alias |
| * dereferencing considerations when enabled during search. |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class ChildrenCursor 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(); |
| |
| /** Error message for unsupported operations */ |
| private static final String UNSUPPORTED_MSG = I18n.err( I18n.ERR_719 ); |
| |
| /** A Cursor over the entries in the scope of the search base */ |
| private final Cursor<IndexEntry<ParentIdAndRdn, String>> cursor; |
| |
| /** The Parent ID */ |
| private String parentId; |
| |
| /** The prefetched element */ |
| private IndexEntry<String, String> prefetched; |
| |
| |
| /** |
| * Creates a Cursor over entries satisfying one level scope criteria. |
| * |
| * @param db the entry store |
| * @param evaluator an IndexEntry (candidate) evaluator |
| * @throws Exception on db access failures |
| */ |
| public ChildrenCursor( Store db, String parentId, Cursor<IndexEntry<ParentIdAndRdn, String>> cursor ) |
| throws Exception |
| { |
| this.parentId = parentId; |
| this.cursor = cursor; |
| |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Creating ChildrenCursor {}", this ); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| protected String getUnsupportedMessage() |
| { |
| return UNSUPPORTED_MSG; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void beforeFirst() throws LdapException, CursorException |
| { |
| checkNotClosed( "beforeFirst()" ); |
| setAvailable( false ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void afterLast() throws LdapException, CursorException |
| { |
| throw new UnsupportedOperationException( getUnsupportedMessage() ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean first() throws LdapException, CursorException |
| { |
| beforeFirst(); |
| |
| return next(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean last() throws LdapException, CursorException |
| { |
| throw new UnsupportedOperationException( getUnsupportedMessage() ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean previous() throws LdapException, CursorException |
| { |
| checkNotClosed( "next()" ); |
| |
| boolean hasPrevious = cursor.previous(); |
| |
| if ( hasPrevious ) |
| { |
| IndexEntry entry = cursor.get(); |
| |
| if ( ( ( ParentIdAndRdn ) entry.getTuple().getKey() ).getParentId().equals( parentId ) ) |
| { |
| prefetched = entry; |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean next() throws LdapException, CursorException |
| { |
| checkNotClosed( "next()" ); |
| |
| boolean hasNext = cursor.next(); |
| |
| if ( hasNext ) |
| { |
| IndexEntry cursorEntry = cursor.get(); |
| IndexEntry<String, String> entry = new IndexEntry(); |
| entry.setId( ( String ) cursorEntry.getId() ); |
| entry.setKey( ( ( ParentIdAndRdn ) cursorEntry.getTuple().getKey() ).getParentId() ); |
| |
| if ( entry.getKey().equals( parentId ) ) |
| { |
| prefetched = entry; |
| return true; |
| } |
| } |
| |
| return false; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public IndexEntry<String, String> get() throws CursorException |
| { |
| checkNotClosed( "get()" ); |
| |
| return prefetched; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void close() |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Closing ChildrenCursor {}", this ); |
| } |
| |
| cursor.close(); |
| |
| super.close(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public void close( Exception cause ) |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Closing ChildrenCursor {}", this ); |
| } |
| |
| cursor.close( cause ); |
| |
| super.close( cause ); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString( String tabs ) |
| { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append( tabs ).append( "ChildrenCursor (" ); |
| |
| if ( available() ) |
| { |
| sb.append( "available)" ); |
| } |
| else |
| { |
| sb.append( "absent)" ); |
| } |
| |
| sb.append( "#parent<" ).append( parentId ).append( "> :\n" ); |
| |
| sb.append( cursor.toString( tabs + " " ) ); |
| |
| return sb.toString(); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString() |
| { |
| return toString( "" ); |
| } |
| } |