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.actions.controls;
021
022
023import org.apache.directory.api.asn1.DecoderException;
024import org.apache.directory.api.asn1.ber.grammar.GrammarAction;
025import org.apache.directory.api.asn1.ber.tlv.TLV;
026import org.apache.directory.api.ldap.codec.api.LdapMessageContainer;
027import org.apache.directory.api.ldap.codec.api.MessageDecorator;
028import org.apache.directory.api.ldap.model.message.Message;
029import org.slf4j.Logger;
030import org.slf4j.LoggerFactory;
031
032
033/**
034 * The action used to initialize a control.
035 * <pre>
036 *         ... },
037 *     controls       [0] Controls OPTIONAL }
038 *     
039 * Controls ::= SEQUENCE OF control Control
040 * </pre>
041 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
042 */
043public class InitControls extends GrammarAction<LdapMessageContainer<MessageDecorator<? extends Message>>>
044{
045    /** The logger */
046    private static final Logger LOG = LoggerFactory.getLogger( InitControls.class );
047
048    /** Speedup for logs */
049    private static final boolean IS_DEBUG = LOG.isDebugEnabled();
050
051
052    /**
053     * Instantiates a new controls init action.
054     */
055    public InitControls()
056    {
057        super( "Initialize a control" );
058    }
059
060
061    /**
062     * {@inheritDoc}
063     */
064    public void action( LdapMessageContainer<MessageDecorator<? extends Message>> container ) throws DecoderException
065    {
066        TLV tlv = container.getCurrentTLV();
067        int expectedLength = tlv.getLength();
068
069        // The Length can be null
070        if ( expectedLength != 0 )
071        {
072            if ( IS_DEBUG )
073            {
074                LOG.debug( "A new list of controls has been initialized" );
075            }
076        }
077        else
078        {
079            if ( IS_DEBUG )
080            {
081                LOG.debug( "An empty list of controls has been initialized" );
082            }
083        }
084
085        // We can have an END transition
086        container.setGrammarEndAllowed( true );
087    }
088}