definitionloaders.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

/* DefinitionLoaders.java

{{IS_NOTE
	Purpose:
		
	Description:
		
	History:
		Mon Aug 29 21:57:08     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.lang.reflect.Field;
import java.util.Iterator;
import java.util.ListIterator;
import java.util.List;
import java.util.LinkedList;
import java.util.Set;
import java.util.HashSet;
import java.util.Map;
import java.util.HashMap;
import java.util.Enumeration;
import java.util.Collections;
import java.net.URL;
import java.io.IOException;

import org.zkoss.lang.D;
import org.zkoss.lang.Classes;
import org.zkoss.util.IllegalSyntaxException;
import org.zkoss.util.logging.Log;
import org.zkoss.util.resource.Locator;
import org.zkoss.util.resource.ClassLocator;
import org.zkoss.idom.Document;
import org.zkoss.idom.Element;
import org.zkoss.idom.ProcessingInstruction;
import org.zkoss.idom.input.SAXBuilder;
import org.zkoss.idom.util.IDOMs;
import org.zkoss.el.Taglib;
import org.zkoss.web.servlet.JavaScript;
import org.zkoss.web.servlet.StyleSheet;

import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.metainfo.LanguageDefinition;
import org.zkoss.zk.ui.metainfo.ComponentDefinition;

/**
 * Utilities to load language definitions.
 *
 * @author tomyeh
 */
public class DefinitionLoaders {
	private static final Log log = Log.lookup(DefinitionLoaders.class);

	private static List _addons = Collections.EMPTY_LIST;

	/** Adds a language addon.
	 *
	 * <p>Note: this method can be called only before definitions have
	 * been loaded.
	 *
	 * @exception IllegalStateException if definitions has been loaded.
	 */
	public static void addLanguage(Locator locator, URL url) {
		if (locator == null || url == null)
			throw new IllegalArgumentException("null");
		if (_addons == null)
			throw new IllegalStateException("Definition has been loaded. You cannot add more.");
		if (_addons == Collections.EMPTY_LIST)
			_addons = new LinkedList();
		_addons.add(new Object[] {locator, url});
	}

	/** Loads all lang.xml found in /metainfo/zk. */
	/*package*/ static void load() {
		final ClassLocator locator = new ClassLocator();

		//1. process lang.xml (no particular dependency)
		try {
			for (Enumeration en = locator.getResources("metainfo/zk/lang.xml");
			en.hasMoreElements();) {
				final URL url = (URL)en.nextElement();
				if (log.debugable()) log.debug("Loading "+url);
				final Document doc = new SAXBuilder(false, false, true).build(url);
				if (checkVersion(url, doc))
					parse(doc, locator, false);
			}
		} catch (Exception ex) {
			throw UiException.Aide.wrap(ex); //abort
		}

		//2. process lang-addon.xml (with dependency)
		try {
			final List xmls = locator.getDependentXMLResources(
				"metainfo/zk/lang-addon.xml", "addon-name", "depends");
			for (Iterator it = xmls.iterator(); it.hasNext();) {
				final ClassLocator.Resource res = (ClassLocator.Resource)it.next();
				if (checkVersion(res.url, res.document)) {
					try {
						parse(res.document, locator, true);
					} catch (Exception ex) {
						log.error("Failed to load addon", ex);
						//keep running
					}
				}
			}
		} catch (Exception ex) {
			log.error("Failed to load addon", ex);
			//keep running
		}

		//3. process other addon (from ConfigParser)
		for (Iterator it = _addons.iterator(); it.hasNext();) {
			final Object[] p = (Object[])it.next();
			final Locator loc = (Locator)p[0];
			final URL url = (URL)p[1];
			try {
				parse(new SAXBuilder(false, false, true).build(url),
					loc, true);
			} catch (Exception ex) {
				log.error("Failed to load addon: "+url, ex);
				//keep running
			}
		}
		_addons = null; //prevent addLanguage being called again
	}

	/** Checks and returns whether the loaded document's version is correct.
	 */
	private static boolean checkVersion(URL url, Document doc) throws Exception {
		final Element el = doc.getRootElement().getElement("version");
		if (el != null) {
			final String clsnm = IDOMs.getRequiredElementValue(el, "version-class");
			final String uid = IDOMs.getRequiredElementValue(el, "version-uid");
			final Class cls = Classes.forNameByThread(clsnm);
			final Field fld = cls.getField("UID");
			final String uidInClass = (String)fld.get(null);
			if (uid.equals(uidInClass)) {
				return true;
			} else {
				log.info("Ignore "+url+"\nCause: version not matched; expected="+uidInClass+", xml="+uid);
				return false;
			}
		} else {
			log.info("Ignore "+url+"\nCause: version not specified");
			return false; //backward compatible
		}
	}

	private static void parse(Document doc, Locator locator, boolean addon)
	throws Exception {
		final Element root = doc.getRootElement();
		final String lang = IDOMs.getRequiredElementValue(root, "language-name");
		final LanguageDefinition langdef;
		if (addon) {
			if (log.debugable()) log.debug("Addon language to "+lang+" from "+root.getElementValue("addon-name", true));
			langdef = LanguageDefinition.lookup(lang);

			if (!root.getElements("case-insensitive").isEmpty())
				throw new UiException("You can not specify case-insensitive in addon");
		} else {
			final String ns = (String)IDOMs.getRequiredElementValue(root, "namespace");
			if (log.debugable()) log.debug("Load language: "+lang+", "+ns);

			String clientType = root.getElementValue("client-type", true);
			if (clientType == null || clientType.length() == 0)
				clientType = "html"; //default

			final Map pagemolds = parseMolds(root);
			final String desktopURI = (String)pagemolds.get("desktop");
			final String pageURI = (String)pagemolds.get("page");
			if (desktopURI == null || pageURI == null)
				throw new IllegalSyntaxException("Both desktop and page molds must be specified, "+root.getLocator());

			final List exts = parseExtensions(root);
			if (exts.isEmpty())
				throw new IllegalSyntaxException("The extension must be specified for "+lang);

			langdef = new LanguageDefinition(
				clientType, lang, ns, exts, desktopURI, pageURI, locator);

			for (Iterator it = root.getElements("case-insensitive").iterator();
			it.hasNext();) {
				final Element el = (Element)it.next();
				final String s = el.getText(true);
				langdef.setCaseInsensitive(!"false".equalsIgnoreCase(s));
			}
		}

		parsePI(langdef, doc);
		parseLabelTemplate(langdef, root);
		parseDynamicTag(langdef, root);
		parseMacroTemplate(langdef, root);

		for (Iterator it = root.getElements("javascript").iterator();
		it.hasNext();) {
			final Element el = (Element)it.next();
			final String src = el.getAttributeValue("src");
			final String ctn = el.getText(true);
			final JavaScript js;
			if (src != null && src.length() > 0) {
				if (ctn != null && ctn.length() > 0)
					throw new UiException("You cannot specify the content if the src attribute is specified, "+el.getLocator());
				final String charset = el.getAttributeValue("charset");
				js = new JavaScript(src, charset);
			} else if (ctn != null && ctn.length() > 0) {
				js = new JavaScript(ctn);
			} else {
				throw new UiException("You must specify either the src attribute or the content, "+el.getLocator());
			}
			langdef.addJavaScript(js);
		}
		for (Iterator it = root.getElements("javascript-module").iterator();
		it.hasNext();) {
			final Element el = (Element)it.next();
			langdef.addJavaScriptModule(
				IDOMs.getRequiredAttributeValue(el, "name"),
				IDOMs.getRequiredAttributeValue(el, "version"));
		}


		for (Iterator it = root.getElements("stylesheet").iterator();
		it.hasNext();) {
			final Element el = (Element)it.next();
			final String href = el.getAttributeValue("href");
			final String ctn = el.getText(true);
			final StyleSheet ss;
			if (href != null && href.length() > 0) {