| /* |
| * 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.partition.impl.btree.jdbm; |
| |
| |
| import org.apache.directory.server.core.avltree.ArrayTree; |
| import org.apache.directory.server.core.avltree.ArrayTreeCursor; |
| import org.apache.directory.server.i18n.I18n; |
| import org.apache.directory.shared.ldap.model.cursor.AbstractTupleCursor; |
| import org.apache.directory.shared.ldap.model.cursor.InvalidCursorPositionException; |
| import org.apache.directory.shared.ldap.model.cursor.Tuple; |
| |
| |
| /** |
| * Cursor over a set of values for the same key which are store in an in |
| * memory ArrayTree. This Cursor is limited to the same key and it's tuples |
| * will always return the same key. |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| public class KeyTupleArrayCursor<K,V> extends AbstractTupleCursor<K,V> |
| { |
| private final ArrayTreeCursor<V> wrapped; |
| private final K key; |
| |
| private Tuple<K,V> returnedTuple = new Tuple<K,V>(); |
| private boolean valueAvailable; |
| |
| |
| /** |
| * Creates a Cursor over the tuples of an ArrayTree. |
| * |
| * @param arrayTree the ArrayTree to build a Tuple returning Cursor over |
| * @param key the constant key for which values are returned |
| */ |
| public KeyTupleArrayCursor( ArrayTree<V> arrayTree, K key ) |
| { |
| this.key = key; |
| this.wrapped = new ArrayTreeCursor<V>( arrayTree ); |
| } |
| |
| |
| private void clearValue() |
| { |
| returnedTuple.setKey( key ); |
| returnedTuple.setValue( null ); |
| valueAvailable = false; |
| } |
| |
| |
| public boolean available() |
| { |
| return valueAvailable; |
| } |
| |
| |
| public void beforeKey( K key ) throws Exception |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| public void afterKey( K key ) throws Exception |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| public void beforeValue( K key, V value ) throws Exception |
| { |
| checkNotClosed( "beforeValue()" ); |
| if ( key != null && ! key.equals( this.key ) ) |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| wrapped.before( value ); |
| clearValue(); |
| } |
| |
| |
| public void afterValue( K key, V value ) throws Exception |
| { |
| checkNotClosed( "afterValue()" ); |
| if ( key != null && ! key.equals( this.key ) ) |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| wrapped.after( value ); |
| clearValue(); |
| } |
| |
| |
| /** |
| * Positions this Cursor over the same keys before the value of the |
| * supplied element Tuple. The supplied element Tuple's key is not |
| * considered at all. |
| * |
| * @param element the valueTuple who's value is used to position this Cursor |
| * @throws Exception if there are failures to position the Cursor |
| */ |
| public void before( Tuple<K,V> element ) throws Exception |
| { |
| checkNotClosed( "before()" ); |
| wrapped.before( element.getValue() ); |
| clearValue(); |
| } |
| |
| |
| public void after( Tuple<K,V> element ) throws Exception |
| { |
| checkNotClosed( "after()" ); |
| wrapped.after( element.getValue() ); |
| clearValue(); |
| } |
| |
| |
| public void beforeFirst() throws Exception |
| { |
| checkNotClosed( "beforeFirst()" ); |
| wrapped.beforeFirst(); |
| clearValue(); |
| } |
| |
| |
| public void afterLast() throws Exception |
| { |
| checkNotClosed( "afterLast()" ); |
| wrapped.afterLast(); |
| clearValue(); |
| } |
| |
| |
| public boolean first() throws Exception |
| { |
| beforeFirst(); |
| return next(); |
| } |
| |
| |
| public boolean last() throws Exception |
| { |
| afterLast(); |
| return previous(); |
| } |
| |
| |
| public boolean previous() throws Exception |
| { |
| checkNotClosed( "previous()" ); |
| if ( wrapped.previous() ) |
| { |
| returnedTuple.setKey( key ); |
| returnedTuple.setValue( wrapped.get() ); |
| return valueAvailable = true; |
| } |
| else |
| { |
| clearValue(); |
| return false; |
| } |
| } |
| |
| |
| public boolean next() throws Exception |
| { |
| checkNotClosed( "next()" ); |
| if ( wrapped.next() ) |
| { |
| returnedTuple.setKey( key ); |
| returnedTuple.setValue( wrapped.get() ); |
| return valueAvailable = true; |
| } |
| else |
| { |
| clearValue(); |
| return false; |
| } |
| } |
| |
| |
| public Tuple<K,V> get() throws Exception |
| { |
| checkNotClosed( "get()" ); |
| if ( valueAvailable ) |
| { |
| return returnedTuple; |
| } |
| |
| throw new InvalidCursorPositionException(); |
| } |
| } |