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.asn1.codec.stateful;
021    
022    
023    import org.apache.directory.shared.asn1.codec.DecoderException;
024    
025    
026    /**
027     * A decoder which decodes encoded data as it arrives in peices while
028     * maintaining the state of the decode operation between the arrival of encoded
029     * chunks. As chunks of encoded data arrive the decoder processes each chunk of
030     * encoded data and maintains decoding state in between arrivals: it is hence
031     * stateful and should be associated with a single channel or encoded data
032     * producer. When an arbitrary unit of encoding, to be determined by the
033     * encoding scheme, has been decoded, the <code>decode()</code> method of the
034     * registered DecoderCallback is called.
035     * 
036     * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
037     * @version $Rev: 664290 $
038     */
039    public interface StatefulDecoder
040    {
041        /**
042         * Decodes a piece of encoded data. The nature of this call, synchronous
043         * verses asynchonous, with respect to driving the actual decoding of the
044         * encoded data argument is determined by an implementation. A return from
045         * this method does not guarantee any callbacks: zero or more callbacks may
046         * occur during this call.
047         * 
048         * @param encoded an object representing a piece of encoded data
049         * @throws DecoderException if the encoded element can't be decoded
050         */
051        void decode( Object encoded ) throws DecoderException;
052    
053    
054        /**
055         * Sets the callback for this StatefulDecoder.
056         * 
057         * @param cb
058         *            the callback to inform of a complete decode operation
059         */
060        void setCallback( DecoderCallback cb );
061    
062    
063        /**
064         * Monitors all kinds of events that occur during processing.
065         * 
066         * @param monitor
067         *            to set for this StatefulDecoder
068         */
069        void setDecoderMonitor( DecoderMonitor monitor );
070    }