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
021package org.apache.directory.api.asn1;
022
023
024/**
025 * <p>
026 * Provides the highest level of abstraction for Decoders. This is the sister
027 * interface of {@link Encoder}. All Decoders implement this common generic
028 * interface.
029 * </p>
030 * <p>
031 * Allows a user to pass a generic Object to any Decoder implementation in the
032 * codec package.
033 * </p>
034 * <p>
035 * One of the two interfaces at the center of the codec package.
036 * </p>
037 * 
038 * @author <a href="mailto:dev@directory.apache.org">Apache Directory Project</a>
039 */
040public interface Decoder
041{
042
043    /**
044     * Decodes an "encoded" Object and returns a "decoded" Object. Note that the
045     * implementation of this interface will try to cast the Object parameter to
046     * the specific type expected by a particular Decoder implementation. If a
047     * {@link java.lang.ClassCastException} occurs this decode method will throw
048     * a DecoderException.
049     * 
050     * @param object an object to "decode"
051     * @return a 'decoded" object
052     * @throws DecoderException a decoder exception can be thrown for any number of reasons.
053     * Some good candidates are that the parameter passed to this method is null, a param 
054     * cannot be cast to the appropriate type for a specific encoder.
055     */
056    Object decode( Object object ) throws DecoderException;
057}