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    package org.apache.shiro.io;
020    
021    /**
022     * A <code>Serializer</code> converts objects to raw binary data and vice versa, enabling persistent storage
023     * of objects to files, HTTP cookies, or other mechanism.
024     * <p/>
025     * A <code>Serializer</code> should only do conversion, never change the data, such as encoding/decoding or
026     * encryption.  These orthogonal concerns are handled elsewhere by Shiro, for example, via
027     * {@link org.apache.shiro.codec.CodecSupport CodecSupport} and {@link org.apache.shiro.crypto.CipherService CipherService}s.
028     *
029     * @author Les Hazlewood
030     * @param <T> The type of the object being serialized and deserialized.
031     * @since 0.9
032     */
033    public interface Serializer<T> {
034    
035        /**
036         * Converts the specified Object into a byte[] array.  This byte[] array must be able to be reconstructed
037         * back into the original Object form via the {@link #deserialize(byte[]) deserialize} method.
038         *
039         * @param o the Object to convert into a byte[] array.
040         * @return a byte[] array representing the Object's state that can be restored later.
041         * @throws SerializationException if an error occurrs converting the Object into a byte[] array.
042         */
043        byte[] serialize(T o) throws SerializationException;
044    
045        /**
046         * Converts the specified raw byte[] array back into an original Object form.  This byte[] array is expected to
047         * be the output of a previous {@link #serialize(Object) serialize} method call.
048         *
049         * @param serialized the raw data resulting from a previous {@link #serialize(Object) serialize} call.
050         * @return the Object that was previously serialized into the raw byte[] array.
051         * @throws SerializationException if an error occurrs converting the raw byte[] array back into an Object.
052         */
053        T deserialize(byte[] serialized) throws SerializationException;
054    }