| /* |
| * 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.core.avltree; |
| |
| |
| import java.util.Collections; |
| import java.util.Comparator; |
| import java.util.List; |
| |
| import org.apache.directory.server.i18n.I18n; |
| |
| |
| /** |
| * An immutable AvlTree wrapping a singleton. |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class AvlTreeSingleton<K> implements AvlTree<K> |
| { |
| private final LinkedAvlNode<K> singleton; |
| private final Comparator<K> comparator; |
| |
| |
| public AvlTreeSingleton( K key, Comparator<K> comparator ) |
| { |
| this.singleton = new LinkedAvlNode<K>( key ); |
| this.comparator = comparator; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> find( K key ) |
| { |
| if ( key != null && comparator.compare( key, singleton.key ) == 0 ) |
| { |
| return singleton; |
| } |
| |
| return null; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> findGreater( K key ) |
| { |
| if ( key != null && comparator.compare( key, singleton.key ) < 0 ) |
| { |
| return singleton; |
| } |
| |
| return null; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> findGreaterOrEqual( K key ) |
| { |
| if ( key != null && comparator.compare( key, singleton.key ) <= 0 ) |
| { |
| return singleton; |
| } |
| |
| return null; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> findLess( K key ) |
| { |
| if ( key != null && comparator.compare( key, singleton.key ) > 0 ) |
| { |
| return singleton; |
| } |
| |
| return null; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> findLessOrEqual( K key ) |
| { |
| if ( key != null && comparator.compare( key, singleton.key ) >= 0 ) |
| { |
| return singleton; |
| } |
| |
| return null; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Comparator<K> getComparator() |
| { |
| return comparator; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> getFirst() |
| { |
| return singleton; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public List<K> getKeys() |
| { |
| return Collections.singletonList( singleton.getKey() ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> getLast() |
| { |
| return singleton; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public LinkedAvlNode<K> getRoot() |
| { |
| return singleton; |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public int getSize() |
| { |
| return 1; |
| } |
| |
| |
| public K insert( K key ) |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_444 ) ); |
| } |
| |
| |
| public boolean isEmpty() |
| { |
| return false; |
| } |
| |
| |
| public void printTree() |
| { |
| System.out.println( "[ " + singleton + " ]" ); |
| } |
| |
| |
| public K remove( K key ) |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_444 ) ); |
| } |
| } |