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.script;
016
017import org.apache.hivemind.ClassResolver;
018import org.apache.hivemind.Resource;
019import org.apache.tapestry.IScript;
020import org.apache.tapestry.coerce.ValueConverter;
021import org.apache.tapestry.services.ExpressionEvaluator;
022import org.apache.tapestry.util.xml.DocumentParseException;
023import 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
051public 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}