1 /*
2  * Licensed to the Apache Software Foundation (ASF) under one or more
3  * contributor license agreements.  See the NOTICE file distributed with
4  * this work for additional information regarding copyright ownership.
5  * The ASF licenses this file to You under the Apache License, Version 2.0
6  * (the "License"); you may not use this file except in compliance with
7  * the License.  You may obtain a copy of the License at
8  *
9  *      http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  */
17 
18 package org.apache.commons.codec;
19 
20 /**
21  * <p>Provides the highest level of abstraction for Decoders.
22  * This is the sister interface of {@link Encoder}.  All
23  * Decoders implement this common generic interface.</p>
24  *
25  * <p>Allows a user to pass a generic Object to any Decoder
26  * implementation in the codec package.</p>
27  *
28  * <p>One of the two interfaces at the center of the codec package.</p>
29  *
30  * @author Apache Software Foundation
31  * @version $Id: Decoder.java 797690 2009-07-24 23:28:35Z ggregory $
32  */
33 public interface Decoder {
34 
35     /**
36      * Decodes an "encoded" Object and returns a "decoded"
37      * Object.  Note that the implementation of this
38      * interface will try to cast the Object parameter
39      * to the specific type expected by a particular Decoder
40      * implementation.  If a {@link ClassCastException} occurs
41      * this decode method will throw a DecoderException.
42      *
43      * @param pObject an object to "decode"
44      *
45      * @return a 'decoded" object
46      *
47      * @throws DecoderException a decoder exception can
48      * be thrown for any number of reasons.  Some good
49      * candidates are that the parameter passed to this
50      * method is null, a param cannot be cast to the
51      * appropriate type for a specific encoder.
52      */
decode(Object pObject)53     Object decode(Object pObject) throws DecoderException;
54 }
55 
56