001// Copyright 2004, 2005 The Apache Software Foundation
002//
003// Licensed under the Apache License, Version 2.0 (the "License");
004// you may not use this file except in compliance with the License.
005// You may obtain a copy of the License at
006//
007//     http://www.apache.org/licenses/LICENSE-2.0
008//
009// Unless required by applicable law or agreed to in writing, software
010// distributed under the License is distributed on an "AS IS" BASIS,
011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
012// See the License for the specific language governing permissions and
013// limitations under the License.
014
015package org.apache.tapestry.util.io;
016
017import org.apache.tapestry.services.DataSqueezer;
018
019/**
020 * Squeezes a String (which is pretty simple, most of the time).
021 * 
022 * @author Howard Lewis Ship
023 */
024
025public class StringAdaptor implements SqueezeAdaptor
026{
027    private static final String PREFIX = "S";
028
029    public String getPrefix()
030    {
031        return PREFIX;
032    }
033
034    public Class getDataClass()
035    {
036        return String.class;
037    }
038
039    public String squeeze(DataSqueezer squeezer, Object data)
040    {
041        String string = (String) data;
042
043        return PREFIX + string;
044    }
045
046    /**
047     * Strips the prefix from the string. This method is only invoked by the
048     * {@link DataSqueezerImpl} if the string leads with its normal prefix (an 'S').
049     */
050
051    public Object unsqueeze(DataSqueezer squeezer, String string)
052    {
053        if (string.length() == 1)
054            return "";
055
056        return string.substring(1);
057    }
058}