pageimpl.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

/* PageImpl.java

{{IS_NOTE
	Purpose:
		
	Description:
		
	History:
		Fri Jun  3 18:17:32     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.impl;

import java.lang.reflect.Method;
import java.util.Iterator;
import java.util.List;
import java.util.LinkedList;
import java.util.ArrayList;
import java.util.Map;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.AbstractMap;
import java.util.Set;
import java.util.HashSet;
import java.util.Collection;
import java.util.Collections;
import java.io.Writer;
import java.io.IOException;

import javax.servlet.jsp.el.FunctionMapper;

import org.zkoss.lang.D;
import org.zkoss.lang.Objects;
import org.zkoss.lang.Strings;
import org.zkoss.lang.Exceptions;
import org.zkoss.lang.Expectable;
import org.zkoss.util.CollectionsX;
import org.zkoss.util.logging.Log;

import org.zkoss.zk.mesg.MZk;
import org.zkoss.zk.ui.Desktop;
import org.zkoss.zk.ui.Page;
import org.zkoss.zk.ui.Session;
import org.zkoss.zk.ui.IdSpace;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.Executions;
import org.zkoss.zk.ui.Execution;
import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.ComponentNotFoundException;
import org.zkoss.zk.ui.event.EventListener;
import org.zkoss.zk.ui.event.Events;
import org.zkoss.zk.ui.metainfo.PageDefinition;
import org.zkoss.zk.ui.metainfo.LanguageDefinition;
import org.zkoss.zk.ui.metainfo.ComponentDefinition;
import org.zkoss.zk.ui.metainfo.ComponentDefinitionMap;
import org.zkoss.zk.ui.metainfo.DefinitionNotFoundException;
import org.zkoss.zk.ui.util.Interpreter;
import org.zkoss.zk.ui.util.Namespace;
import org.zkoss.zk.ui.util.VariableResolver;
import org.zkoss.zk.ui.sys.ExecutionCtrl;
import org.zkoss.zk.ui.sys.WebAppCtrl;
import org.zkoss.zk.ui.sys.DesktopCtrl;
import org.zkoss.zk.ui.sys.PageCtrl;
import org.zkoss.zk.ui.sys.ComponentCtrl;
import org.zkoss.zk.ui.sys.ComponentsCtrl;
import org.zkoss.zk.ui.sys.Variables;
import org.zkoss.zk.ui.sys.UiEngine;
import org.zkoss.zk.ui.impl.bsh.BshInterpreter;
import org.zkoss.zk.au.AuSetTitle;

/**
 * An implmentation of {@link Page} and {@link PageCtrl}.
 * Refer to them for more details.
 *
 * <p>Note: though {@link PageImpl} is serializable, it is designed
 * to work with Web container to enable the serialization of sessions.
 * It is not suggested to serialize and desrialize it directly since
 * many fields might be lost.
 *
 * <p>On the other hand, it is OK to serialize and deserialize
 * {@link Component}.
 *
 * <p>Implementation Notes:<br>
 * It is not thread-safe because it is protected by the spec:
 * at most one thread can access a page and all its components at the same time.
 *
 * @author tomyeh
 */
public class PageImpl implements Page, PageCtrl, java.io.Serializable {
	private static final Log log = Log.lookup(PageImpl.class);
	private static final Log _zklog = Log.lookup("org.zkoss.zk.log");
    private static final long serialVersionUID = 20060707L;

	/** URI for redrawing as a desktop or part of another desktop. */
	private final String _dkUri, _pgUri;
	/** The component that includes this page, or null if not included. */
	private transient Component _owner;
	/** Used to retore _owner. */
	private transient String _ownerUuid;
	private transient Desktop _desktop;
	private String _id;
	private transient Interpreter _ip;
	private String _title = "", _style = "";
	private final String _path;
	/** A list of root components. */
	private final List _roots = new LinkedList();
	private transient List _roRoots;
	/** A map of fellows. */
	private transient Map _fellows;
	/** A map of attributes. */
	private transient Map _attrs;
		//don't create it dynamically because _ip bind it at constructor
	/** A map of event listener: Map(evtnm, List(EventListener)). */
	private transient Map _listeners;
	/** The default parent. */
	private transient Component _defparent;
	/** The reason to store it is PageDefinition is not serializable. */
	private FunctionMapper _funmap;
	/** The reason to store it is PageDefinition is not serializable. */
	private ComponentDefinitionMap _compdefs;
	/** The reason to store it is PageDefinition is not serializable. */
	private transient LanguageDefinition _langdef;
	/** The header tags. */
	private String _headers = "";

	/** Constructs a page by giving the page definition.
	 *
	 * <p>Note: when a page is constructed, it doesn't belong to a desktop
	 * yet. Caller has to invoke {@link #init} to complete
	 * the creation of a page.
	 * Why two phase? Contructor could be called before execution
	 * is activated, but {@link #init} must be called in an execution.
	 *
	 * <p>Also note that {@link #getId} and {@link #getTitle}
	 * are not ready until {@link #init} is called.
	 *
	 * @param pgdef the page definition (never null).
	 */
	public PageImpl(PageDefinition pgdef) {
		_langdef = pgdef.getLanguageDefinition();
		_dkUri = _langdef.getDesktopURI();
		_pgUri = _langdef.getPageURI();
		_compdefs = pgdef.getComponentDefinitionMap();
		_path = pgdef.getRequestPath();

		init();
	}
	/** Constructs a page by giving the language definition. It is mainly
	 * used to create a page for {@link org.zkoss.zk.ui.Richlet}.
	 *
	 * <p>Note: when a page is constructed, it doesn't belong to a desktop
	 * yet. Caller has to invoke {@link #init} to complete
	 * the creation of a page.
	 *
	 * <p>Also note that {@link #getId} and {@link #getTitle}
	 * are not ready until {@link #init} is called.
	 *
	 * @param langdef the language definition (never null).
	 * @param path the request path, or null if not available
	 */
	public PageImpl(LanguageDefinition langdef, String path) {
		_langdef = langdef;
		_dkUri = _langdef.getDesktopURI();
		_pgUri = _langdef.getPageURI();
		_compdefs = new ComponentDefinitionMap();
		_path = path != null ? path: "";

		init();
	}
	/** Initialized the page when contructed or deserialized.
	 */
	protected void init() {
		_ip = new BshInterpreter();
		_roRoots = Collections.unmodifiableList(_roots);
		_attrs = new HashMap();
		_fellows = new HashMap();
	}

	/** Returns the UI engine.
	 */
	private final UiEngine getUiEngine() {
		return ((WebAppCtrl)_desktop.getWebApp()).getUiEngine();
	}

	//-- Page --//
	private final Execution getExecution() {
		return _desktop != null ? _desktop.getExecution():
			Executions.getCurrent();
	}
	public final FunctionMapper getFunctionMapper() {
		return _funmap;
	}
	public void addFunctionMapper(FunctionMapper funmap) {
		if (funmap != null)
			if (_funmap != null)
				_funmap = new DualFuncMapper(funmap, _funmap);
			else
				_funmap = funmap;
	}

	public String getRequestPath() {
		return _path;
	}
	public final String getId() {
		return _id;
	}
	public void setId(String id) {
		if (_desktop != null)
			throw new UiException("Unable to change the identifier after the page is initialized");
		if (id != null && id.length() > 0) _id = id;
		//No need to update client since it is allowed only before init(...)
	}
	public String getTitle() {
		return _title;
	}
	public void setTitle(String title) {
		if (title == null) title = "";
		if (!_title.equals(title)) {
			_title = title;
			if (_desktop != null) {
				final Execution exec = getExecution();
				if (_title.length() > 0) {
					_title = (String)exec.evaluate(this, _title, String.class);
					if (_title == null) _title = "";
				}

				if (exec.isAsyncUpdate(this))
					getUiEngine().addResponse("setTitle", new AuSetTitle(_title));
			}
		}
	}
	public String getStyle() {
		return _style;
	}
	public void setStyle(String style) {
		if (style == null) style = "";
		if (!_style.equals(style)) {
			_style = style;
			if (_desktop != null) {
				final Execution exec = getExecution();
				if (_style.length() > 0) {
					_style = (String)exec.evaluate(this, _style, String.class);
					if (_style == null) _style = "";
				}
				//FUTURE: might support the change of style dynamically
			}
		}
	}

	public Collection getRoots() {
		return _roRoots;
	}

	public Map getAttributes(int scope) {
		switch (scope) {
		case DESKTOP_SCOPE:
			return _desktop != null ?
				_desktop.getAttributes(): Collections.EMPTY_MAP;
		case SESSION_SCOPE:
			return _desktop != null ?
				_desktop.getSession().getAttributes(): Collections.EMPTY_MAP;
		case APPLICATION_SCOPE:
			return _desktop != null ?
				_desktop.getWebApp().getAttributes(): Collections.EMPTY_MAP;
		case PAGE_SCOPE:
			return _attrs;
		case REQUEST_SCOPE:
			final Execution exec = getExecution();
			if (exec != null) return exec.getAttributes();
			//fall thru
		default:
			return Collections.EMPTY_MAP;
		}
	}
	public Object getAttribute(String name, int scope) {
		return getAttributes(scope).get(name);
	}
	public Object setAttribute(String name, Object value, int scope) {
		if (value != null) {
			final Map attrs = getAttributes(scope);
			if (attrs == Collections.EMPTY_MAP)
				throw new IllegalStateException("This component doesn't belong to any ID space: "+this);
			return attrs.put(name, value);
		} else {
			return removeAttribute(name, scope);
		}
	}
	public Object removeAttribute(String name, int scope) {
			final Map attrs = getAttributes(scope);
			if (attrs == Collections.EMPTY_MAP)
				throw new IllegalStateException("This component doesn't belong to any ID space: "+this);
		return attrs.remove(name);
	}

	public Map getAttributes() {
		return _attrs;
	}
	public Object getAttribute(String name) {
		return _attrs.get(name);
	}
	public Object setAttribute(String name, Object value) {
		return value != null ? _attrs.put(name, value): removeAttribute(name);
	}
	public Object removeAttribute(String name) {
		return _attrs.remove(name);
	}

	public void invalidate() {
		getUiEngine().addInvalidate(this);
	}
	public void removeComponents() {
		for (Iterator it = new ArrayList(getRoots()).iterator();
		it.hasNext();)
			((Component)it.next()).detach();
	}

	public void setVariable(String name, Object val) {
		_ip.setVariable(name, val);
	}
	public Object getVariable(String name) {
		return _ip.getVariable(name);
	}
	public void unsetVariable(String name) {
		_ip.unsetVariable(name);
	}

	public boolean addVariableResolver(VariableResolver resolver) {
		return _ip.addVariableResolver(resolver);
	}
	public boolean removeVariableResolver(VariableResolver resolver) {
		return _ip.removeVariableResolver(resolver);
	}

	public Object resolveElVariable(String name) {
		try {
			final javax.servlet.jsp.el.VariableResolver resolv =
				getExecution().getVariableResolver();
			return resolv != null ? resolv.resolveVariable(name): null;
		} catch (javax.servlet.jsp.el.ELException ex) {
			throw UiException.Aide.wrap(ex);
		}
	}

	public boolean addEventListener(String evtnm, EventListener listener) {
		if (evtnm == null || listener == null)
			throw new IllegalArgumentException("null");
		if (!Events.isValid(evtnm))
			throw new IllegalArgumentException("Invalid event name: "+evtnm);
		if (listener.isAsap())
			log.warning("Ignored: ASAP is meaningless if an event listener added to a page: "+listener);

		if (_listeners == null)
			_listeners = new HashMap(3);

		List l = (List)_listeners.get(evtnm);
		if (l != null) {
			for (Iterator it = l.iterator(); it.hasNext();) {
				final EventListener li = (EventListener)it.next();
				if (listener.equals(li))