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     */
020    package org.apache.directory.shared.ldap.message.control;
021    
022    
023    /**
024     * Protocol request and response altering control interface. Any number of
025     * controls may be associated with a protocol message.
026     * 
027     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
028     * @version $Rev: 764131 $
029     */
030    public interface Control
031    {
032        /**
033         * @return The Control's OID
034         */
035        String getOid();
036        
037        
038        /**
039         * Tells if the control is critical or not.
040         *
041         * @return <code>true/code> if the control is critical, <code>false</code> otherwise 
042         */
043        boolean isCritical();
044        
045        
046        /**
047         * Sets the critical flag which determines whether or not this control is
048         * critical for the correct operation of a request or response message. The
049         * default for this value should be false.
050         * 
051         * @param isCritical true if the control is critical false otherwise.
052         */
053        void setCritical( boolean isCritical );
054        
055        
056        /**
057         * Returns the encoded value for this Control
058         *
059         * @return The encoded value
060         */
061        byte[] getValue();
062        
063        
064        /**
065         * Stores the encoded value for this Control
066         *
067         * @param value The encoded value
068         */
069        void setValue( byte[] value );
070        
071        
072        /**
073         * Tells if the Control has a value or not
074         *
075         * @return <code>true</code> if th Control has a value, even containing no bytes.
076         */
077        boolean hasValue();
078    }