avl-partition/src/main/java/org/apache/directory/server/core/partition/avl/AvlIndex.java

/*
 *   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.avl;


import org.apache.directory.server.core.cursor.Cursor;
import org.apache.directory.server.xdbm.Index;
import org.apache.directory.server.xdbm.IndexCursor;
import org.apache.directory.server.xdbm.IndexCursorAdaptor;
import org.apache.directory.server.xdbm.NoNormalizerOnIndexException;
import org.apache.directory.server.xdbm.Tuple;
import org.apache.directory.shared.ldap.schema.AttributeType;
import org.apache.directory.shared.ldap.schema.MatchingRule;
import org.apache.directory.shared.ldap.schema.Normalizer;


/**
 * An Index backed by an AVL Tree.
 *
 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
 * @version $Rev$, $Date$
 */
public class AvlIndex<K,O> implements Index<K, O>
{
    private Normalizer normalizer;
    private AttributeType attributeType;
    private AvlTable<K,Long> forward;
    private AvlTable<Long,K> reverse;
    private String attributeId;
    
    
    public AvlIndex() throws Exception
    {
    }
    
    
    void initialize( AttributeType attributeType ) throws Exception
    {
        this.attributeType = attributeType;

        MatchingRule mr = attributeType.getEquality();
        
        if ( mr == null )
        {
            mr = attributeType.getOrdering();
        }
        
        if ( mr == null )
        {
            mr = attributeType.getSubstr();
        }

        normalizer = mr.getNormalizer();
        
        if ( normalizer == null )
        {
            throw new NoNormalizerOnIndexException();
        }
    }

    
    public void add( K attrVal, Long id ) throws Exception
    {
        forward.put( attrVal, id );
    }


    /**
     * {@inheritDoc}
     */
    public void close() throws Exception
    {
        forward.close();
        reverse.close();
    }


    /**
     * {@inheritDoc}
     */
    public int count() throws Exception
    {
        return forward.count();
    }


    /**
     * {@inheritDoc}
     */
    public int count( K attrVal ) throws Exception
    {
        return forward.count( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public void drop( Long id ) throws Exception
    {
        Cursor<Tuple<Long,K>> cursor = reverse.cursor( id );
        
        while ( cursor.next() )
        {
            Tuple<Long,K> tuple = cursor.get();
            forward.remove( tuple.getValue(), id );
        }
        
        reverse.remove( id );
    }


    /**
     * {@inheritDoc}
     */
    public void drop( K attrVal, Long id ) throws Exception
    {
        forward.remove( attrVal, id );
        reverse.remove( id, attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean forward( K attrVal ) throws Exception
    {
        return forward.has( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean forward( K attrVal, Long id ) throws Exception
    {
        return forward.has( attrVal, id );
    }


    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public IndexCursor<K, O> forwardCursor() throws Exception
    {
        return new IndexCursorAdaptor( forward.cursor(), true );
    }


    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public IndexCursor<K, O> forwardCursor( K key ) throws Exception
    {
        return new IndexCursorAdaptor( forward.cursor( key ), true );
    }


    /**
     * {@inheritDoc}
     */
    public boolean forwardGreaterOrEq( K attrVal ) throws Exception
    {
        return forward.hasGreaterOrEqual( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean forwardGreaterOrEq( K attrVal, Long id ) throws Exception
    {
        return forward.hasGreaterOrEqual( attrVal, id );
    }


    /**
     * {@inheritDoc}
     */
    public boolean forwardLessOrEq( K attrVal ) throws Exception
    {
        return forward.hasLessOrEqual( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean forwardLessOrEq( K attrVal, Long id ) throws Exception
    {
        return forward.hasLessOrEqual( attrVal, id );
    }


    /**
     * {@inheritDoc}
     */
    public Long forwardLookup( K attrVal ) throws Exception
    {
        return forward.get( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public Cursor<Long> forwardValueCursor( K key ) throws Exception
    {
        return forward.valueCursor( key );
    }


    /**
     * {@inheritDoc}
     */
    public AttributeType getAttribute()
    {
        return attributeType;
    }


    /**
     * {@inheritDoc}
     */
    public String getAttributeId()
    {
        return attributeId;
    }


    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public K getNormalized( K attrVal ) throws Exception
    {
        return ( K ) normalizer.normalize( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public int greaterThanCount( K attrVal ) throws Exception
    {
        return forward.greaterThanCount( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean isCountExact()
    {
        return false;
    }


    /**
     * {@inheritDoc}
     */
    public int lessThanCount( K attrVal ) throws Exception
    {
        return forward.lessThanCount( attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean reverse( Long id ) throws Exception
    {
        return reverse.has( id );
    }


    /**
     * {@inheritDoc}
     */
    public boolean reverse( Long id, K attrVal ) throws Exception
    {
        return reverse.has( id, attrVal );
    }


    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public IndexCursor<K, O> reverseCursor() throws Exception
    {
        return new IndexCursorAdaptor( reverse.cursor(), false );
    }


    /**
     * {@inheritDoc}
     */
    @SuppressWarnings("unchecked")
    public IndexCursor<K, O> reverseCursor( Long id ) throws Exception
    {
        return new IndexCursorAdaptor( reverse.cursor( id ), false );
    }


    /**
     * {@inheritDoc}
     */
    public boolean reverseGreaterOrEq( Long id ) throws Exception
    {
        return reverse.hasGreaterOrEqual( id );
    }


    /**
     * {@inheritDoc}
     */
    public boolean reverseGreaterOrEq( Long id, K attrVal ) throws Exception
    {
        return reverse.hasGreaterOrEqual( id, attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public boolean reverseLessOrEq( Long id ) throws Exception
    {
        return reverse.hasLessOrEqual( id );
    }

    
    /**
     * {@inheritDoc}
     */
    public boolean reverseLessOrEq( Long id, K attrVal ) throws Exception
    {
        return reverse.hasLessOrEqual( id, attrVal );
    }


    /**
     * {@inheritDoc}
     */
    public K reverseLookup( Long id ) throws Exception
    {
        return reverse.get( id );
    }


    /**
     * {@inheritDoc}
     */
    public Cursor<K> reverseValueCursor( Long id ) throws Exception
    {
        return reverse.valueCursor( id );
    }


    /**
     * {@inheritDoc}
     */
    public void setAttributeId( String attributeId )
    {
        this.attributeId = attributeId;
    }


    /**
     * {@inheritDoc}
     */
    public void sync() throws Exception
    {
    }
}