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 * Provides the highest level of abstraction for Decoders. 22 * <p> 23 * This is the sister interface of {@link Encoder}. All Decoders implement this common generic interface. 24 * Allows a user to pass a generic Object to any Decoder implementation in the codec package. 25 * </p> 26 * <p> 27 * One of the two interfaces at the center of the codec package. 28 * </p> 29 */ 30 public interface Decoder { 31 32 /** 33 * Decodes an "encoded" Object and returns a "decoded" Object. Note that the implementation of this interface will 34 * try to cast the Object parameter to the specific type expected by a particular Decoder implementation. If a 35 * {@link ClassCastException} occurs this decode method will throw a DecoderException. 36 * 37 * @param source 38 * the object to decode 39 * @return a 'decoded" object 40 * @throws DecoderException 41 * a decoder exception can be thrown for any number of reasons. Some good candidates are that the 42 * parameter passed to this method is null, a param cannot be cast to the appropriate type for a 43 * specific encoder. 44 */ 45 Object decode(Object source) throws DecoderException; 46 } 47