parser.java

非常接近C/S操作方式的Java Ajax框架－ZK 用ZK框架使你的B/S应用程序更漂亮更易操作。 官网：www.zkoss.org

/* Parser.java

{{IS_NOTE
	Purpose:
		
	Description:
		
	History:
		Tue May 31 14:26:18     2005, Created by tomyeh
}}IS_NOTE

Copyright (C) 2005 Potix Corporation. All Rights Reserved.

{{IS_RIGHT
	This program is distributed under GPL Version 2.0 in the hope that
	it will be useful, but WITHOUT ANY WARRANTY.
}}IS_RIGHT
*/
package org.zkoss.zk.ui.metainfo;

import java.util.List;
import java.util.LinkedList;
import java.util.Collections;
import java.util.Iterator;
import java.util.Collection;
import java.util.Map;
import java.util.HashMap;
import java.util.Set;
import java.util.LinkedHashSet;
import java.io.File;
import java.io.Reader;
import java.io.FileNotFoundException;
import java.net.URL;

import org.zkoss.lang.D;
import org.zkoss.lang.Classes;
import org.zkoss.lang.PotentialDeadLockException;
import org.zkoss.util.Maps;
import org.zkoss.util.logging.Log;
import org.zkoss.util.resource.Locator;
import org.zkoss.idom.Namespace;
import org.zkoss.idom.Document;
import org.zkoss.idom.Element;
import org.zkoss.idom.Text;
import org.zkoss.idom.CData;
import org.zkoss.idom.Item;
import org.zkoss.idom.Attribute;
import org.zkoss.idom.ProcessingInstruction;
import org.zkoss.idom.util.IDOMs;
import org.zkoss.idom.input.SAXBuilder;
import org.zkoss.el.Taglib;
import org.zkoss.web.servlet.Servlets;

import org.zkoss.zk.ui.WebApp;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.event.Events;
import org.zkoss.zk.ui.impl.ZScriptInitiator;
import org.zkoss.zk.ui.util.Condition;
import org.zkoss.zk.ui.util.ConditionImpl;
import org.zkoss.zk.ui.sys.WebAppCtrl;
import org.zkoss.zk.ui.sys.RequestInfo;
import org.zkoss.zk.ui.sys.UiFactory;
import org.zkoss.zk.ui.impl.RequestInfoImpl;

/**
 * Used to prase the ZUL file
 * @author tomyeh
 */
public class Parser {
	private static final Log log = Log.lookup(Parser.class);

	private final WebApp _wapp;
	private final Locator _locator;

	/** Constructor.
	 *
	 * @param locator the locator used to locate taglib and other resources.
	 * If null, wapp is assumed ({@link WebApp} is also assumed).
	 */	
	public Parser(WebApp wapp, Locator locator) {
		if (wapp == null)
			throw new IllegalArgumentException("null");
		_wapp = wapp;
		_locator = locator != null ? locator: (Locator)wapp;
	}

	/** Parses the specified file.
	 *
	 * @param path the request path.
	 * It is used as {@link org.zkoss.zk.ui.Page#getRequestPath}, or null
	 * if not available.
	 */
	public PageDefinition parse(File file, String path) throws Exception {
		//if (log.debugable()) log.debug("Parsing "+file);
		final PageDefinition pgdef =
			parse(new SAXBuilder(true, false, true).build(file),
				getExtension(file.getName()));
		pgdef.setRequestPath(path);
		return pgdef;
	}
	/** Parses the specified URL.
	 *
	 * @param path the request path.
	 * It is used as {@link org.zkoss.zk.ui.Page#getRequestPath}, or null
	 * if not available.
	 */
	public PageDefinition parse(URL url, String path) throws Exception {
		//if (log.debugable()) log.debug("Parsing "+url);
		final PageDefinition pgdef =
			parse(new SAXBuilder(true, false, true).build(url),
				getExtension(url.toExternalForm()));
		pgdef.setRequestPath(path);
		return pgdef;
	}

	private static final String getExtension(String nm) {
		int j = nm == null ? -1: nm.lastIndexOf('.');
		if (j < 0 || j < nm.lastIndexOf('/'))
			return null;

		final StringBuffer sb = new StringBuffer(8);
		for (final int len = nm.length(); ++j < len;) {
			final char cc = nm.charAt(j);
			if ((cc < 'a' || cc > 'z') && (cc < 'A' || cc > 'Z')
			&& (cc < '0' || cc > '9'))
				break;
			sb.append(cc);
		}
		return sb.toString();
	}
	/** Parses from the specified reader.
	 *
	 * @param extension the default extension if doc (of reader) doesn't specify
	 * an language. Ignored if null.
	 * If extension is null and the content doesn't specify a language,
	 * the language called "xul/html" is assumed.
	 */
	public PageDefinition parse(Reader reader, String extension)
	throws Exception {
		//if (log.debugable()) log.debug("Parsing "+reader);
		return parse(new SAXBuilder(true, false, true).build(reader), extension);
	}
	/** Parss the raw content directly from a DOM tree.
	 *
	 * @param extension the default extension if doc doesn't specify
	 * an language. Ignored if null.
	 * If extension is null and the content doesn't specify a language,
	 * the language called "xul/html" is assumed.
	 */
	public PageDefinition parse(Document doc, String extension)
	throws Exception {
		//1. parse the page and import directive if any
		final List pis = new LinkedList();
		final List imports = new LinkedList();
		String lang = null, title = null, id = null, style = null;
		for (Iterator it = doc.getChildren().iterator(); it.hasNext();) {
			final Object o = it.next();
			if (!(o instanceof ProcessingInstruction)) continue;

			final ProcessingInstruction pi = (ProcessingInstruction)o;
			final String target = pi.getTarget();
			if ("page".equals(target)) {
				for (Iterator i2 = pi.parseData().entrySet().iterator(); i2.hasNext();) {
					final Map.Entry me = (Map.Entry)i2.next();
					final String nm = (String)me.getKey();
					final String val = (String)me.getValue();
					if ("language".equals(nm)) {
						lang = val;
						noEL("language", lang, pi);
					} else if ("title".equals(nm)) {
						title = val;
					} else if ("style".equals(nm)) {
						style = val;
					} else if ("id".equals(nm)) {
						id = val;
					} else {
						log.warning("Ignored unknown attribute: "+nm+", "+pi.getLocator());
					}
				}
			} else if ("import".equals(target)) { //import
				final Map params = pi.parseData();
				final String src = (String)params.remove("src");
				if (isEmpty(src))
					throw new UiException("The src attribute is required, "+pi.getLocator());
				if (!params.isEmpty())
					log.warning("Ignored unknown attributes: "+params.keySet()+", "+pi.getLocator());
				noEL("src", src, pi);
				imports.add(src);
			} else {
				pis.add(pi);
			}
		}

		//2. Create PageDefinition
		final LanguageDefinition langdef =
			extension != null && lang == null?
				LanguageDefinition.getByExtension(extension):
				LanguageDefinition.lookup(lang);
		final PageDefinition pgdef =
			new PageDefinition(langdef, id, title, style, getLocator());

		//3. resolve imports
		if (!imports.isEmpty()) {
			final RequestInfo ri =
				new RequestInfoImpl(_wapp, null, null, null, _locator);
			final UiFactory uf = ((WebAppCtrl)_wapp).getUiFactory();
			for (Iterator it = imports.iterator(); it.hasNext();) {
				final String path = (String)it.next();
				try {
					final PageDefinition pd = uf.getPageDefinition(ri, path);
					if (pd == null)
						throw new UiException("Import page not found: "+path);
					pgdef.imports(pd);
				} catch (PotentialDeadLockException ex) {
					throw new UiException("Recursive import: "+path, ex);
				}
			}
		}

		//4. Processing the rest of processing instructions at the top level
		for (Iterator it = pis.iterator(); it.hasNext();)
			parse(pgdef, (ProcessingInstruction)it.next());

		//5. Processing from the root element
		final Element root = doc.getRootElement();
		if (root != null) parse(pgdef, pgdef, root, new AnnotInfo());
		return pgdef;
	}
	private static Class locateClass(String clsnm) throws Exception {
		try {
			return Classes.forNameByThread(clsnm);
		} catch (ClassNotFoundException ex) {
			throw new ClassNotFoundException("Class not found: "+clsnm, ex);
		}
	}

	//-- derive to override --//
	/** returns locator for locating resources. */
	public Locator getLocator() {
		return _locator;
	}

	/** Parse processing instruction.
	 */
	private void parse(PageDefinition pgdef, ProcessingInstruction pi)
	throws Exception {
		final String target = pi.getTarget();
		final Map params = pi.parseData();
		if ("taglib".equals(target)) {
			final String uri = (String)params.remove("uri");
			final String prefix = (String)params.remove("prefix");
			if (!params.isEmpty())
				log.warning("Ignored unknown attributes: "+params.keySet()+", "+pi.getLocator());
			if (uri == null || prefix == null)
				throw new UiException("Both uri and prefix attribute are required, "+pi.getLocator());
			//if (D.ON && log.debugable()) log.debug("taglib: prefix="+prefix+" uri="+uri);
			noEL("prefix", prefix, pi);
			noEL("uri", uri, pi); //not support EL (kind of chicken-egg issue)
			pgdef.addTaglib(new Taglib(prefix, toAbsoluteURI(uri, false)));
		} else if ("init".equals(target)) {
			final List args = new LinkedList();
			for (int j = 0;; ++j) {
				final String arg = (String)params.remove("arg" + j);
				if (arg == null) break;
				args.add(arg);
			}

			final String clsnm = (String)params.remove("class");
			final String zsrc = (String)params.remove("zscript");

			if (!params.isEmpty())
				log.warning("Ignored unknown attributes: "+params.keySet()+", "+pi.getLocator());

			if (isEmpty(clsnm)) {
				if (isEmpty(zsrc))
					throw new UiException("Either the class or zscript attribute must be specified, "+pi.getLocator());

				final ZScript zs;
				if (zsrc.indexOf("${") >= 0) {
					zs = new ZScript(zsrc, null, getLocator());
				} else {
					final URL url = getLocator().getResource(zsrc);
					if (url == null) throw new FileNotFoundException("File not found: "+zsrc+", at "+pi.getLocator());
					zs = new ZScript(url, null);
				}

				pgdef.addInitiatorDefinition(
					new InitiatorDefinition(new ZScriptInitiator(zs), args));
			} else {
				if (!isEmpty(zsrc))
					throw new UiException("You cannot specify both class and zscript, "+pi.getLocator());

				pgdef.addInitiatorDefinition(
					clsnm.indexOf("${") >= 0 ? //class supports EL
						new InitiatorDefinition(clsnm, args):
						new InitiatorDefinition(locateClass(clsnm), args));
					//Note: we don't resolve the class name later because
					//no zscript run before init (and better performance)
			}
		} else if ("variable-resolver".equals(target)) {
			final String clsnm = (String)params.remove("class");
			if (isEmpty(clsnm))
				throw new UiException("The class attribute is required, "+pi.getLocator());
			if (!params.isEmpty())
				log.warning("Ignored unknown attributes: "+params.keySet()+", "+pi.getLocator());

			pgdef.addVariableResolverDefinition(
				clsnm.indexOf("${") >= 0 ? //class supports EL
					new VariableResolverDefinition(clsnm):
					new VariableResolverDefinition(locateClass(clsnm)));
		} else if ("component".equals(target)) { //declare a component
			final String name = (String)params.remove("name");
			if (isEmpty(name)) throw new UiException("name is required, "+pi.getLocator());
			noEL("name", name, pi); //note: macro-uri supports EL

			final String macroURI = (String)params.remove("macro-uri");
			final String extds = (String)params.remove("extends");
			final String clsnm = (String)params.remove("class");
			ComponentDefinition compdef;
			if (macroURI != null) {
				//if (D.ON && log.finerable()) log.finer("macro component definition: "+name);

				noEL("macro-uri", macroURI, pi);
					//no EL because pagedef must be loaded to resolve
					//the impl class before creating an instance of macro

				compdef = new ComponentDefinition(
					null, name, toAbsoluteURI(macroURI, false));
				pgdef.getLanguageDefinition().initMacroDefinition(compdef);
				if (!isEmpty(clsnm)) {
					noEL("class", clsnm, pi);
					compdef.setImplementationClass(clsnm);
						//Resolve later since might defined in zscript
				}
			} else if (extds != null) { //extends
				//if (D.ON && log.finerable()) log.finer("Override component definition: "+name);

				noEL("extends", extds, pi);
				final ComponentDefinition ref = pgdef.getLanguageDefinition()
					.getComponentDefinition(extds);
				if (ref.isMacro())
					throw new UiException("Unable to extend from a macro component, "+pi.getLocator());

				compdef = (ComponentDefinition)ref.clone(name);
				compdef.setLanguageDefinition(null);
				if (!isEmpty(clsnm)) {
					noEL("class", clsnm, pi);
					compdef.setImplementationClass(clsnm);
						//Resolve later since might defined in zscript
				}
			} else {
				//if (D.ON && log.finerable()) log.finer("Add component definition: name="+name);

				if (isEmpty(clsnm)) throw new UiException("class is required");
				noEL("class", clsnm, pi);

				compdef = new ComponentDefinition(null, name, (Class)null);
				compdef.setImplementationClass(clsnm);
					//Resolve later since might be defined in zscript
			}

			pgdef.addComponentDefinition(compdef);

			final String moldnm = (String)params.remove("mold-name");
			noEL("mold-name", moldnm, pi);
			final String moldURI = (String)params.remove("mold-uri");
			if (!isEmpty(moldURI))
				compdef.addMold(isEmpty(moldnm) ? "default": moldnm,