| /* |
| * 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.mavibot.btree; |
| |
| |
| import java.io.IOException; |
| |
| import org.apache.directory.mavibot.btree.exception.EndOfFileExceededException; |
| import org.apache.directory.mavibot.btree.exception.KeyNotFoundException; |
| import org.apache.directory.mavibot.btree.BTree; |
| |
| |
| /** |
| * A class that encapsulate the values into an sub-btree |
| * |
| * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a> |
| */ |
| /* No qualifier */class ValueBTreeCursor<V> implements ValueCursor<V> |
| { |
| /** Store the current position in the array or in the BTree */ |
| private KeyCursor<V> cursor; |
| |
| /** The Value sub-btree */ |
| private BTree<V, V> valueBtree; |
| |
| |
| /** |
| * Create an instance |
| */ |
| public ValueBTreeCursor( BTree<V, V> valueBtree ) |
| { |
| this.valueBtree = valueBtree; |
| |
| // Start at -1 to be positioned before the first element |
| try |
| { |
| if ( valueBtree != null ) |
| { |
| cursor = valueBtree.browseKeys(); |
| } |
| } |
| catch ( IOException e ) |
| { |
| // TODO Auto-generated catch block |
| e.printStackTrace(); |
| } |
| catch ( KeyNotFoundException knfe ) |
| { |
| // TODO Auto-generated catch block |
| knfe.printStackTrace(); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| @Override |
| public boolean hasNext() |
| { |
| if ( cursor == null ) |
| { |
| return false; |
| } |
| else |
| { |
| try |
| { |
| return cursor.hasNext(); |
| } |
| catch ( EndOfFileExceededException e ) |
| { |
| e.printStackTrace(); |
| return false; |
| } |
| catch ( IOException e ) |
| { |
| e.printStackTrace(); |
| return false; |
| } |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| public V next() |
| { |
| try |
| { |
| return cursor.next(); |
| } |
| catch ( EndOfFileExceededException e ) |
| { |
| e.printStackTrace(); |
| return null; |
| } |
| catch ( IOException e ) |
| { |
| e.printStackTrace(); |
| return null; |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| @Override |
| public boolean hasPrev() throws EndOfFileExceededException, IOException |
| { |
| if ( cursor == null ) |
| { |
| return false; |
| } |
| else |
| { |
| try |
| { |
| return cursor.hasPrev(); |
| } |
| catch ( EndOfFileExceededException e ) |
| { |
| e.printStackTrace(); |
| return false; |
| } |
| catch ( IOException e ) |
| { |
| e.printStackTrace(); |
| return false; |
| } |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| @Override |
| public void close() |
| { |
| if ( cursor != null ) |
| { |
| cursor.close(); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| @Override |
| public void beforeFirst() throws IOException |
| { |
| if ( cursor != null ) |
| { |
| cursor.beforeFirst(); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| @Override |
| public void afterLast() throws IOException |
| { |
| if ( cursor != null ) |
| { |
| cursor.afterLast(); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc}} |
| */ |
| @Override |
| public V prev() throws EndOfFileExceededException, IOException |
| { |
| try |
| { |
| return cursor.prev(); |
| } |
| catch ( EndOfFileExceededException e ) |
| { |
| e.printStackTrace(); |
| return null; |
| } |
| catch ( IOException e ) |
| { |
| e.printStackTrace(); |
| return null; |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| @Override |
| public int size() |
| { |
| return ( int ) valueBtree.getNbElems(); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString() |
| { |
| return "BTreeCursor"; |
| } |
| } |