001//  Copyright 2008, 2009, 2010 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.tapestry5.dom;
016
017public abstract class AbstractMarkupModel implements MarkupModel
018{
019    private final boolean useApostropheForAttributes;
020    private final char attributeQuoteChar;
021
022    protected AbstractMarkupModel(boolean useApostropheForAttributes)
023    {
024        this.useApostropheForAttributes = useApostropheForAttributes;
025        this.attributeQuoteChar = useApostropheForAttributes ? '\'' : '"';
026    }
027
028    public char getAttributeQuote()
029    {
030        return attributeQuoteChar;
031    }
032
033    /**
034     * Passes all characters but '<', '>' and '&' through unchanged.
035     */
036    public String encode(String content)
037    {
038        int length = content.length();
039
040        StringBuilder builder = null;
041
042        for (int i = 0; i < length; i++)
043        {
044            char ch = content.charAt(i);
045
046            switch (ch)
047            {
048                case '<':
049
050                    if (builder == null)
051                    {
052                        builder = new StringBuilder(2 * length);
053
054                        builder.append(content.substring(0, i));
055                    }
056
057                    builder.append("&lt;");
058                    continue;
059
060                case '>':
061
062                    if (builder == null)
063                    {
064                        builder = new StringBuilder(2 * length);
065
066                        builder.append(content.substring(0, i));
067                    }
068
069                    builder.append("&gt;");
070                    continue;
071
072                case '&':
073
074                    if (builder == null)
075                    {
076                        builder = new StringBuilder(2 * length);
077
078                        builder.append(content.substring(0, i));
079                    }
080
081                    builder.append("&amp;");
082                    continue;
083
084                default:
085
086                    if (builder != null)
087                        builder.append(ch);
088            }
089        }
090
091        return builder == null ? content : builder.toString();
092    }
093
094    public void encodeQuoted(String content, StringBuilder builder)
095    {
096        assert content != null;
097        int length = content.length(), tokenStart = 0, i = 0;
098        builder.ensureCapacity(builder.length() + length);
099        String delimiter;
100        for (; i < length; i++)
101        {
102            char ch = content.charAt(i);
103
104            switch (ch)
105            {
106                case '<':
107
108                    delimiter = "&lt;";
109                    break;
110
111                case '>':
112
113                    delimiter = "&gt;";
114                    break;
115
116                case '&':
117
118                    delimiter = "&amp;";
119                    break;
120
121                case '"':
122
123                    if (!useApostropheForAttributes)
124                    {
125                        delimiter = "&quot;";
126                        break;
127                    }
128
129                    continue;
130
131                case '\'':
132
133                    if (useApostropheForAttributes)
134                    {
135                        //TAP5-714
136                        delimiter = "&#39;";
137                        break;
138                    }
139
140
141                    continue;
142
143
144                default:
145
146                    continue;
147            }
148
149            if (tokenStart != i)
150            {
151                builder.append(content.subSequence(tokenStart, i));
152            }
153
154            builder.append(delimiter);
155
156            tokenStart = i + 1;
157        }
158
159        if (tokenStart != length)
160        {
161            builder.append(content.subSequence(tokenStart, length));
162        }
163    }
164}