001/*
002 *  Licensed to the Apache Software Foundation (ASF) under one
003 *  or more contributor license agreements.  See the NOTICE file
004 *  distributed with this work for additional information
005 *  regarding copyright ownership.  The ASF licenses this file
006 *  to you under the Apache License, Version 2.0 (the
007 *  "License"); you may not use this file except in compliance
008 *  with the License.  You may obtain a copy of the License at
009 *  
010 *    http://www.apache.org/licenses/LICENSE-2.0
011 *  
012 *  Unless required by applicable law or agreed to in writing,
013 *  software distributed under the License is distributed on an
014 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
015 *  KIND, either express or implied.  See the License for the
016 *  specific language governing permissions and limitations
017 *  under the License. 
018 *  
019 */
020package org.apache.directory.api.ldap.codec.search;
021
022
023import java.nio.ByteBuffer;
024
025import org.apache.directory.api.asn1.EncoderException;
026
027
028/**
029 * An abstract Asn1Object used to store the filter. A filter is seen as a tree
030 * with a root. This class does nothing, it's just the root of all the different
031 * filters.
032 * 
033 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
034 */
035public abstract class Filter
036{
037    /** The identifier of the associated TLV */
038    int tlvId;
039
040    /** The parent TLV id */
041    protected int parentTlvId;
042
043    /** The parent Filter */
044    protected Filter parent;
045
046
047    /**
048     * The constructor.
049     */
050    public Filter( int tlvId )
051    {
052        this.tlvId = tlvId;
053    }
054
055
056    /**
057     * The constructor.
058     */
059    public Filter()
060    {
061    }
062
063
064    /**
065     * Get the parent
066     * 
067     * @return Returns the parent.
068     */
069    public Filter getParent()
070    {
071        return parent;
072    }
073
074
075    /**
076     * Get the parent
077     * 
078     * @return Returns the parent.
079     */
080    public int getParentTlvId()
081    {
082        return parentTlvId;
083    }
084
085
086    /**
087     * Set the parent
088     * 
089     * @param parent The parent to set.
090     */
091    public void setParent( Filter parent, int parentTlvId )
092    {
093        this.parent = parent;
094        this.parentTlvId = parentTlvId;
095    }
096
097
098    public int getTlvId()
099    {
100        return tlvId;
101    }
102
103
104    /**
105     * Compute the Filter length 
106     */
107    public abstract int computeLength();
108
109
110    /**
111     * Encode the Filter message to a PDU. 
112     * @param buffer The buffer where to put the PDU
113     * @return The PDU.
114     */
115    public abstract ByteBuffer encode( ByteBuffer buffer ) throws EncoderException;
116}