| /* |
| * 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.mavibot; |
| |
| |
| import java.io.IOException; |
| |
| import org.apache.directory.api.ldap.model.constants.Loggers; |
| import org.apache.directory.api.ldap.model.cursor.AbstractCursor; |
| 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.cursor.Tuple; |
| import org.apache.directory.api.ldap.model.exception.LdapException; |
| import org.apache.directory.mavibot.btree.ValueCursor; |
| import org.apache.directory.server.i18n.I18n; |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| |
| /** |
| * 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 KeyTupleValueCursor<K, V> extends AbstractCursor<Tuple<K, V>> |
| { |
| /** 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 final ValueCursor<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 KeyTupleValueCursor( ValueCursor<V> cursor, K key ) |
| { |
| this.key = key; |
| |
| this.wrapped = cursor; |
| |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Creating KeyTupleArrayCursor {}", this ); |
| } |
| } |
| |
| |
| 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 |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| public void afterValue( K key, V value ) throws Exception |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| /** |
| * 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 LdapException, CursorException |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void after( Tuple<K, V> element ) throws LdapException, CursorException |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void beforeFirst() throws LdapException, CursorException |
| { |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void afterLast() throws LdapException, CursorException |
| { |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean first() throws LdapException, CursorException |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean last() throws LdapException, CursorException |
| { |
| throw new UnsupportedOperationException( I18n.err( I18n.ERR_446 ) ); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean previous() throws LdapException, CursorException |
| { |
| checkNotClosed( "previous()" ); |
| |
| try |
| { |
| if ( wrapped.hasPrev() ) |
| { |
| returnedTuple.setKey( key ); |
| returnedTuple.setValue( wrapped.prev() ); |
| valueAvailable = true; |
| return true; |
| } |
| else |
| { |
| clearValue(); |
| return false; |
| } |
| } |
| catch ( IOException e ) |
| { |
| throw new CursorException( e ); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public boolean next() throws LdapException, CursorException |
| { |
| checkNotClosed( "next()" ); |
| |
| try |
| { |
| if ( wrapped.hasNext() ) |
| { |
| returnedTuple.setKey( key ); |
| returnedTuple.setValue( wrapped.next() ); |
| |
| valueAvailable = true; |
| return true; |
| } |
| else |
| { |
| clearValue(); |
| |
| return false; |
| } |
| } |
| catch ( IOException e ) |
| { |
| throw new CursorException( e ); |
| } |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public Tuple<K, V> get() throws CursorException |
| { |
| checkNotClosed( "get()" ); |
| |
| if ( valueAvailable ) |
| { |
| return returnedTuple; |
| } |
| |
| throw new InvalidCursorPositionException(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void close() throws IOException |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Closing KeyTupleArrayCursor {}", this ); |
| } |
| |
| if ( wrapped != null ) |
| { |
| wrapped.close(); |
| } |
| |
| super.close(); |
| } |
| |
| |
| /** |
| * {@inheritDoc} |
| */ |
| public void close( Exception reason ) throws IOException |
| { |
| if ( IS_DEBUG ) |
| { |
| LOG_CURSOR.debug( "Closing KeyTupleArrayCursor {}", this ); |
| } |
| |
| if ( wrapped != null ) |
| { |
| wrapped.close(); |
| } |
| |
| super.close( reason ); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString( String tabs ) |
| { |
| StringBuilder sb = new StringBuilder(); |
| |
| sb.append( tabs ).append( "KeyTupleArrayCursor (" ); |
| |
| if ( available() ) |
| { |
| sb.append( "available)" ); |
| } |
| else |
| { |
| sb.append( "absent)" ); |
| } |
| |
| sb.append( "#" ).append( key ); |
| |
| sb.append( " :\n" ); |
| |
| sb.append( wrapped.toString() ); |
| |
| return sb.toString(); |
| } |
| |
| |
| /** |
| * @see Object#toString() |
| */ |
| public String toString() |
| { |
| return toString( "" ); |
| } |
| } |