001    /**
002     *
003     *  Licensed to the Apache Software Foundation (ASF) under one or more
004     *  contributor license agreements.  See the NOTICE file distributed with
005     *  this work for additional information regarding copyright ownership.
006     *  The ASF licenses this file to You under the Apache License, Version 2.0
007     *  (the "License"); you may not use this file except in compliance with
008     *  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, software
013     *  distributed under the License is distributed on an "AS IS" BASIS,
014     *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
015     *  See the License for the specific language governing permissions and
016     *  limitations under the License.
017     */
018    
019    package org.apache.geronimo.util.encoders;
020    
021    /**
022     * Convert binary data to and from UrlBase64 encoding.  This is identical to
023     * Base64 encoding, except that the padding character is "." and the other
024     * non-alphanumeric characters are "-" and "_" instead of "+" and "/".
025     * <p>
026     * The purpose of UrlBase64 encoding is to provide a compact encoding of binary
027     * data that is safe for use as an URL parameter. Base64 encoding does not
028     * produce encoded values that are safe for use in URLs, since "/" can be
029     * interpreted as a path delimiter; "+" is the encoded form of a space; and
030     * "=" is used to separate a name from the corresponding value in an URL
031     * parameter.
032     */
033    public class UrlBase64Encoder extends Base64Encoder
034    {
035        public UrlBase64Encoder()
036        {
037            encodingTable[encodingTable.length - 2] = (byte) '-';
038            encodingTable[encodingTable.length - 1] = (byte) '_';
039            padding = (byte) '.';
040            // we must re-create the decoding table with the new encoded values.
041            initialiseDecodingTable();
042        }
043    }