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    
015    package org.apache.tapestry.script;
016    
017    import org.apache.hivemind.ClassResolver;
018    import org.apache.hivemind.Resource;
019    import org.apache.tapestry.IScript;
020    import org.apache.tapestry.coerce.ValueConverter;
021    import org.apache.tapestry.services.ExpressionEvaluator;
022    import org.apache.tapestry.util.xml.DocumentParseException;
023    import org.apache.tapestry.util.xml.RuleDirectedParser;
024    
025    /**
026     * Parses a Tapestry Script, an XML file defined by one of the following public identifiers:
027     * <ul>
028     * <li><code>-//Primix Solutions//Tapestry Script 1.0//EN</code></li>
029     * <li><code>-//Howard Ship//Tapestry Script 1.1//EN</code></li>
030     * <li><code>-//Howard Lewis Ship//Tapestry Script 1.2//EN</code></li>.
031     * <p>
032     * The version 1.1, is largely backwards compatible to the old script, but adds a number of new
033     * features (if, if-not, foreach and the use of property paths with insert).
034     * <p>
035     * Version 1.2 removes the &lt;insert&gt; element, using an Ant-like syntax (
036     * <code>${<i>expression</i>}</code>). It also replaces the attribute name
037     * <code>property-path</code> with <code>expression</code> (because OGNL is used).
038     * <p>
039     * A Tapestry Script is used, in association with the {@link org.apache.tapestry.html.Body}and/or
040     * {@link org.apache.tapestry.html.Script}components, to generate JavaScript for use with a
041     * Tapestry component. Two seperate pieces of JavaScript can be generated. The body section
042     * (associated with the <code>body</code> element of the XML document) is typically used to define
043     * JavaScript functions (most often, event handlers). The initialization section (associated with
044     * the <code>initialization</code> element of the XML document) is used to add JavaScript that
045     * will be evaluated when the page finishes loading (i.e., from the HTML &lt;body&gt; element's
046     * onLoad event handler).
047     * 
048     * @author Howard Lewis Ship
049     */
050    
051    public class ScriptParser
052    {
053        private RuleDirectedParser _parser;
054    
055        public static final String SCRIPT_DTD_1_0_PUBLIC_ID = "-//Primix Solutions//Tapestry Script 1.0//EN";
056    
057        public static final String SCRIPT_DTD_1_1_PUBLIC_ID = "-//Howard Ship//Tapestry Script 1.1//EN";
058    
059        public static final String SCRIPT_DTD_1_2_PUBLIC_ID = "-//Howard Lewis Ship//Tapestry Script 1.2//EN";
060    
061        /** @since 3.0 */
062        public static final String SCRIPT_DTD_3_0_PUBLIC_ID = "-//Apache Software Foundation//Tapestry Script Specification 3.0//EN";
063    
064        public ScriptParser(ClassResolver resolver, ExpressionEvaluator evaluator,
065                ValueConverter valueConverter)
066        {
067            _parser = new RuleDirectedParser();
068    
069            _parser.registerEntity(
070                    SCRIPT_DTD_1_0_PUBLIC_ID,
071                    "/org/apache/tapestry/script/Script_1_0.dtd");
072            _parser.registerEntity(
073                    SCRIPT_DTD_1_1_PUBLIC_ID,
074                    "/org/apache/tapestry/script/Script_1_1.dtd");
075            _parser.registerEntity(
076                    SCRIPT_DTD_1_2_PUBLIC_ID,
077                    "/org/apache/tapestry/script/Script_1_2.dtd");
078            _parser.registerEntity(
079                    SCRIPT_DTD_3_0_PUBLIC_ID,
080                    "/org/apache/tapestry/script/Script_3_0.dtd");
081    
082            _parser.addRule("script", new ScriptRule(evaluator, valueConverter));
083            _parser.addRule("let", new LetRule());
084            _parser.addRule("set", new SetRule());
085            _parser.addRule("include-script", new IncludeScriptRule());
086            _parser.addRule("input-symbol", new InputSymbolRule(resolver));
087            _parser.addRule("body", new BodyRule());
088            _parser.addRule("initialization", new InitRule());
089            _parser.addRule("if", new IfRule(true));
090            _parser.addRule("if-not", new IfRule(false));
091            _parser.addRule("foreach", new ForeachRule());
092            _parser.addRule("unique", new UniqueRule());
093    
094            // This will go away when the 1.1 and earler DTDs are retired.
095            _parser.addRule("insert", new InsertRule());
096    
097        }
098    
099        /**
100         * Parses the given input stream to produce a parsed script, ready to execute.
101         */
102    
103        public IScript parse(Resource resourceLocation) throws DocumentParseException
104        {
105            return (IScript) _parser.parse(resourceLocation);
106        }
107    
108    }