001 /**
002 * GRANITE DATA SERVICES
003 * Copyright (C) 2006-2013 GRANITE DATA SERVICES S.A.S.
004 *
005 * This file is part of the Granite Data Services Platform.
006 *
007 * Granite Data Services is free software; you can redistribute it and/or
008 * modify it under the terms of the GNU Lesser General Public
009 * License as published by the Free Software Foundation; either
010 * version 2.1 of the License, or (at your option) any later version.
011 *
012 * Granite Data Services is distributed in the hope that it will be useful,
013 * but WITHOUT ANY WARRANTY; without even the implied warranty of
014 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser
015 * General Public License for more details.
016 *
017 * You should have received a copy of the GNU Lesser General Public
018 * License along with this library; if not, write to the Free Software
019 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301,
020 * USA, or see <http://www.gnu.org/licenses/>.
021 */
022
023 package org.granite.generator.gsp;
024
025 import java.io.BufferedReader;
026 import java.io.IOException;
027 import java.io.Reader;
028 import java.io.StringReader;
029 import java.util.ArrayList;
030 import java.util.List;
031
032 import org.granite.generator.gsp.token.Comment;
033 import org.granite.generator.gsp.token.Declaration;
034 import org.granite.generator.gsp.token.Directive;
035 import org.granite.generator.gsp.token.Expression;
036 import org.granite.generator.gsp.token.Scriplet;
037 import org.granite.generator.gsp.token.TemplateText;
038 import org.granite.generator.gsp.token.Token;
039
040 /**
041 * @author Franck WOLFF
042 */
043 public class Parser {
044
045 private final List<Token> elements = new ArrayList<Token>();
046
047 public Parser() {
048 }
049
050 public List<Token> parse(Reader reader) throws IOException, ParseException {
051 if (reader == null)
052 throw new NullPointerException("reader cannot be null");
053 if (!(reader instanceof StringReader || reader instanceof BufferedReader))
054 reader = new BufferedReader(reader);
055 return parse(read(reader));
056 }
057
058 public List<Token> getElements() {
059 return elements;
060 }
061
062 public void reset() {
063 elements.clear();
064 }
065
066 private List<Token> parse(String template) throws ParseException {
067 if (template == null)
068 throw new NullPointerException("Argument template cannot be null");
069
070 StringBuilder sb = new StringBuilder(64);
071
072 final int length = template.length();
073 boolean inText = true;
074 for (int i = 0; i < length; i++) {
075 char first = inText ? '<' : '%';
076 char last = inText ? '%' : '>';
077 char c = template.charAt(i);
078 boolean appendC = true;
079
080 if (c == first) { // '<' (template text) or '%' (gsp tag content)
081 if (i+1 < length) {
082 c = template.charAt(i+1);
083 if (c == last) { // "<%" (template text) or "%>" (gsp tag content)
084 if (inText)
085 addTemplateText(i - sb.length(), sb.toString());
086 else
087 addScriptingElement(i - sb.length() - 2, sb.toString());
088 sb.setLength(0);
089 inText = !inText;
090 appendC = false;
091 i++;
092 } else if (c == '\\') { // "<\" (template text) or "%\" (gsp tag content)
093 sb.append(first);
094 for (i += 2; i < length && (c = template.charAt(i)) == '\\'; i++)
095 sb.append(c);
096 if (c != last) // add skiped first '/'
097 sb.append('\\');
098 } else
099 c = first;
100 }
101 }
102
103 if (appendC)
104 sb.append(c);
105 }
106
107 if (!inText)
108 throw new ParseException("Missing script section end (\"%>\")");
109
110 addTemplateText(length - sb.length(), sb.toString());
111
112 return elements;
113 }
114
115 private String read(Reader reader) throws IOException {
116 StringBuilder sb = new StringBuilder(1024);
117
118 int pc = -1, c = -1;
119 while((c = reader.read()) != -1) {
120 switch (c) {
121 case '\r': // "\r[\n]" (Windows or Mac)
122 break;
123 case '\n': // "[\r]\n" (Windows or Unix)
124 sb.append('\n');
125 break;
126 default:
127 if (pc == '\r') // "\r" (Mac)
128 sb.append('\n');
129 sb.append((char)c);
130 break;
131 }
132 pc = c;
133 }
134
135 return sb.toString();
136 }
137
138 private void addTemplateText(int index, String text) {
139 if (text.length() > 0)
140 elements.add(new TemplateText(index, text));
141 }
142
143 private void addScriptingElement(int index, String text) throws ParseException {
144 if (text.length() == 0)
145 return;
146 char first = text.charAt(0);
147 switch (first) {
148 case '=': // expression
149 elements.add(new Expression(index, text.substring(1).trim()));
150 break;
151 case '!': // variable or method declaration
152 elements.add(new Declaration(index, text.substring(1).trim()));
153 break;
154 case '@': // directive
155 elements.add(new Directive(index, text.substring(1).trim()));
156 break;
157 case '-': // comment ?
158 if (text.startsWith("--") && text.endsWith("--")) {
159 elements.add(new Comment(index, text.substring(2, text.length() - 4)));
160 break;
161 }
162 // fall down (scriplet starting with '-')...
163 default: // scriplet
164 elements.add(new Scriplet(index, text));
165 break;
166 }
167 }
168 }