databinder.java

ZK 基础介绍 功能操作 模块 结合数据库操作

/* DataBinder.java

{{IS_NOTE
	Purpose:
		
	Description:
		
	History:
		Thu Feb  1 18:27:18     2007, Created by Henri
}}IS_NOTE

Copyright (C) 2006 Potix Corporation. All Rights Reserved.

{{IS_RIGHT
}}IS_RIGHT
*/
package org.zkoss.zkplus.databind;

import org.zkoss.zk.ui.Page;
import org.zkoss.zk.ui.Path;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.sys.ComponentCtrl;
import org.zkoss.zk.ui.metainfo.Annotation; 
import org.zkoss.zk.ui.event.Event;
import org.zkoss.zk.ui.event.Events;
import org.zkoss.zk.ui.event.EventListener;
import org.zkoss.zk.scripting.Namespace;
import org.zkoss.zk.scripting.Interpreter;
import org.zkoss.zk.scripting.HierachicalAware;

import org.zkoss.zul.Row;
import org.zkoss.zul.Listitem;
import org.zkoss.zul.ListModel;

import org.zkoss.util.ModificationException;
import org.zkoss.lang.Objects;
import org.zkoss.lang.Primitives;
import org.zkoss.lang.reflect.Fields;

import java.util.Map;
import java.util.Set;
import java.util.Date;
import java.util.Map.Entry;
import java.util.List;
import java.util.HashSet;
import java.util.Iterator;
import java.util.ArrayList;
import java.util.ListIterator;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Collection;
import java.util.LinkedHashMap;
import java.util.LinkedHashSet;

/**
 * The DataBinder used for binding ZK UI component and the backend data bean.
 *
 * @author Henri Chen
 */
public class DataBinder {
	public static final String NULLIFY = "none"; //used to nullify default configuration
	public static final String VARNAME = "zkplus.databind.VARNAME"; //_var name
	public static final String TEMPLATEMAP = "zkplus.databind.TEMPLATEMAP"; // template -> clone
	public static final String TEMPLATE = "zkplus.databind.TEMPLATE"; //clone -> template
	private static final String OWNER = "zkplus.databind.OWNER"; //the collection owner of the template component
	private static final String HASTEMPLATEOWNER = "zkplus.databind.HASTEMPLATEOWNER"; //whether has template owner (collection in collection)
	private static final Object NA = new Object();

	private Map _compBindingMap = new LinkedHashMap(29); //(comp, Map(attr, Binding))
	private Map _beans = new HashMap(29); //bean local to this DataBinder
	private Map _beanSameNodes = new HashMap(29); //(bean, Set(BindingNode)) bean same nodes, diff expression but actually hold the same bean
	private BindingNode _pathTree = new BindingNode("/", false, "/", false); //path dependency tree.
	private boolean _defaultConfig = true; //whether load default configuration from lang-addon.xml
	private boolean _init; //whether this databinder is initialized. 
	private EventListener _listener = new LoadOnSaveEventListener();
		//Databinder is init automatically when saveXXX or loadXxx is called
	
	protected Map _collectionItemMap = new HashMap(3);
	
	/** Binding bean to UI component. This is the same as 
	 * addBinding(Component comp, String attr, String expr, (List)null, (List)null, (String)null, (String)null). 
	 * @param comp The component to be associated.
	 * @param attr The attribute of the component to be associated.
	 * @param expr The expression to associate the data bean.
	 */
	public void addBinding(Component comp, String attr, String expr) {
		addBinding(comp, attr, expr, (List)null, (List)null, null, null);
	}

	/** Binding bean to UI component. 
	 * @param comp The component to be associated.
	 * @param attr The attribute of the component to be associated.
	 * @param expr The expression to associate the data bean.
	 * @param loadWhenEvents The event list when to load data.
	 * @param saveWhenEvent The event when to save data.
	 * @param access In the view of UI component: "load" load only, 
	 * "both" load/save, "save" save only when doing
	 * data binding. null means using the default access natural of the component. 
	 * e.g. Label.value is "load", but Textbox.value is "both".
	 * @param converter The converter class used to convert classes between component 
	 *  and the associated bean. null means using the default class conversion method.
	 */
	public void addBinding(Component comp, String attr, String expr,
		String[] loadWhenEvents, String saveWhenEvent, String access, String converter) {
		List loadEvents = null;
		if (loadWhenEvents != null && loadWhenEvents.length > 0) {
			loadEvents = new ArrayList(loadWhenEvents.length);
			for (int j = 0; j < loadWhenEvents.length; ++j) {
				loadEvents.add(loadWhenEvents[j]);
			}
		}
		addBinding(comp, attr, expr, loadEvents, saveWhenEvent, access, converter);
	}
	
	/** Binding bean to UI component. 
	 * @param comp The component to be associated.
	 * @param attr The attribute of the component to be associated.
	 * @param expr The expression to associate the data bean.
	 * @param loadWhenEvents The event list when to load data.
	 * @param saveWhenEvents The event when to save data.
	 * @param access In the view of UI component: "load" load only, 
	 * "both" load/save, "save" save only when doing
	 * data binding. null means using the default access natural of the component. 
	 * e.g. Label.value is "load", but Textbox.value is "both".
	 * @param converter The converter class used to convert classes between component 
	 *  and the associated bean. null means using the default class conversion method.
	 * @since 3.0.0
	 */
	public void addBinding(Component comp, String attr, String expr,
		String[] loadWhenEvents, String[] saveWhenEvents, String access, String converter) {
		List loadEvents = null;
		if (loadWhenEvents != null && loadWhenEvents.length > 0) {
			loadEvents = new ArrayList(loadWhenEvents.length);
			for (int j = 0; j < loadWhenEvents.length; ++j) {
				loadEvents.add(loadWhenEvents[j]);
			}
		}
		List saveEvents = null;
		if (saveWhenEvents != null && saveWhenEvents.length > 0) {
			saveEvents = new ArrayList(saveWhenEvents.length);
			for (int j = 0; j < saveWhenEvents.length; ++j) {
				saveEvents.add(saveWhenEvents[j]);
			}
		}
		addBinding(comp, attr, expr, loadEvents, saveEvents, access, converter);
	}
	
	/** Binding bean to UI component. 
	 * @param comp The component to be associated.
	 * @param attr The attribute of the component to be associated.
	 * @param expr The expression to associate the data bean.
	 * @param loadWhenEvents The event list when to load data.
	 * @param saveWhenEvent The event when to save data.
	 * @param access In the view of UI component: "load" load only, 
	 * "both" load/save, "save" save only when doing
	 * data binding. null means using the default access natural of the component. 
	 * e.g. Label.value is "load", but Textbox.value is "both".
	 * @param converter The converter class used to convert classes between component 
	 *  and the associated bean. null means using the default class conversion method.
	 */
	public void addBinding(Component comp, String attr, String expr,
		List loadWhenEvents, String saveWhenEvent, String access, String converter) {
		List saveEvents = new ArrayList(1);
		saveEvents.add(saveWhenEvent);
		addBinding(comp, attr, expr, loadWhenEvents, saveEvents, access, converter);
	}
	
	/** Binding bean to UI component. 
	 * @param comp The component to be associated.
	 * @param attr The attribute of the component to be associated.
	 * @param expr The expression to associate the data bean.
	 * @param loadWhenEvents The event list when to load data.
	 * @param saveWhenEvents The event list when to save data.
	 * @param access In the view of UI component: "load" load only, 
	 * "both" load/save, "save" save only when doing
	 * data binding. null means using the default access natural of the component. 
	 * e.g. Label.value is "load", but Textbox.value is "both".
	 * @param converter The converter class used to convert classes between component 
	 *  and the associated bean. null means using the default class conversion method.
	 * @since 3.0.0
	 */
	public void addBinding(Component comp, String attr, String expr,
		List loadWhenEvents, List saveWhenEvents, String access, String converter) {
			
		//Since 2.5, 20070726, Henri Chen: we accept "each" to replace "_var" in collection data binding
		//Before 2.4.1
		//<a:bind _var="person">
		//<listitem...>
		//After 2.5
		//<listitem self="@{bind(each='person')}"...>
		//or <listitem self="@{each='person'}"...>
		if ("each".equals(attr)) {
			attr = "_var";
		}
			
		if (isDefaultConfig()) { //use default binding configuration
			//handle default-bind defined in lang-addon.xml
			Object[] objs = loadPropertyAnnotation(comp, attr, "default-bind");
			
			/* logically impossible to hold "expr" in default binding 
			if (expr == null && objs[0] != null) {
				expr = (String) objs[0];
			}
			*/

			if (loadWhenEvents == null && objs[1] != null) {
				loadWhenEvents = (List) objs[1];
			}
			if (saveWhenEvents == null && objs[2] != null) {
				saveWhenEvents = (List) objs[2];
			}
			if (access == null && objs[3] != null) {
				access = (String) objs[3];
			}
			if (converter == null && objs[4] != null) {
				converter = (String) objs[4];
			}
		}
	
		//nullify check
		boolean nullify = false;
		LinkedHashSet loadEvents = null;
		if (loadWhenEvents != null && loadWhenEvents.size() > 0) {
			loadEvents = new LinkedHashSet(loadWhenEvents.size());
			for(final Iterator it = loadWhenEvents.iterator(); it.hasNext();) {
				final String event = (String) it.next();
				if (NULLIFY.equals(event)) {
					loadEvents.clear();
					nullify = true;
				} else {
					nullify = false;
					loadEvents.add(event);
				}
			}
			if (loadEvents.isEmpty()) { 
				loadEvents = null;
			}
		}

		nullify = false;
		Set saveEvents = null;
		if (saveWhenEvents != null && saveWhenEvents.size() > 0) {
			saveEvents = new HashSet(saveWhenEvents.size());
			for(final Iterator it = saveWhenEvents.iterator(); it.hasNext();) {
				final String event = (String) it.next();
				if (NULLIFY.equals(event)) {
					saveEvents.clear();
					nullify = true;
				} else {
					nullify = false;
					saveEvents.add(event);
				}
			}
			if (saveEvents.isEmpty()) { 
				saveEvents = null;
			}
		}

		if (NULLIFY.equals(access)) {
			access = null;
		}
		
		if (NULLIFY.equals(converter)) {
			converter = null;
		}
		
		Map attrMap = (Map) _compBindingMap.get(comp);
		if (attrMap == null) {
			attrMap = new LinkedHashMap(3);
			_compBindingMap.put(comp, attrMap);
		}
			
		if (attrMap.containsKey(attr)) { //override
			final Binding binding = (Binding) attrMap.get(attr);
			binding.setExpression(expr);
			binding.setLoadWhenEvents(loadEvents);
			binding.setSaveWhenEvents(saveEvents);
			binding.setAccess(access);
			binding.setConverter(converter);
		} else {
			attrMap.put(attr, new Binding(this, comp, attr, expr, loadEvents, saveEvents, access, converter));
		}
	}
	
	/** Remove the binding associated with the attribute of the component.
	 * @param comp The component to be removed the data binding association.
	 * @param attr The attribute of the component to be removed the data binding association.
	 */
	public void removeBinding(Component comp, String attr) {
		Map attrMap = (Map) _compBindingMap.get(comp);
		if (attrMap != null) {
			attrMap.remove(attr);
		}
	}

	/** Given component and attr, return the associated {@link Binding}.
	 * @param comp the concerned component
	 * @param attr the concerned attribute
	 */
	public Binding getBinding(Component comp, String attr) {
		if (isClone(comp)) {
			comp = (Component) comp.getAttribute(TEMPLATE);
		}
		Map attrMap = (Map) _compBindingMap.get(comp);
		return attrMap != null ?  (Binding) attrMap.get(attr) : null;
	}

	/** Given component, return the associated list of {@link Binding}s.
	 * @param comp the concerned component
	 */
	public Collection getBindings(Component comp) {
		if (isClone(comp)) {
			comp = (Component) comp.getAttribute(TEMPLATE);
		}
		Map attrMap = (Map)_compBindingMap.get(comp);
		return attrMap != null ?  (Collection) attrMap.values() : null;
	}
	
	/** Whether this component associated with any bindings.
	 */
	public boolean existsBindings(Component comp) {
		if (isClone(comp)) {
			comp = (Component) comp.getAttribute(TEMPLATE);
		}
		return _compBindingMap.containsKey(comp);
	}
	
	/** Whether this component and attribute associated with a binding.
	 */
	public boolean existBinding(Component comp, String attr) {
		if (isClone(comp)) {
			comp = (Component) comp.getAttribute(TEMPLATE);
		}
		if (_compBindingMap.containsKey(comp)) {
			Map attrMap = (Map) _compBindingMap.get(comp);
			return attrMap.containsKey(attr);
		}
		return false;
	}		
	
	/** Whether use the default binding configuration.
	 */
	public boolean isDefaultConfig(){
		return _defaultConfig;
	}
	
	/** Whether use the default binding configuration.
	 */
	public void setDefaultConfig(boolean b) {
		_defaultConfig = b;
	}
	
	/** Bind a real bean object to the specified beanid. You might not need to call this method because this
	 * DataBinder would look up the variable via the {@link org.zkoss.zk.ui.Component#getVariable} method
	 * if it cannot find the specified bean via the given beanid.
	 *
	 * @param beanid The bean id used in data binding.
	 * @param bean The real bean object to be associated with the bean id.
	 */
	public void bindBean(String beanid, Object bean) {
		_beans.put(beanid, bean);
	}
	
	
	/** Load value from the data bean property to a specified attribute of the UI component.
	 * @param comp the UI component to be loaded value.
	 * @param attr the UI component attribute to be loaded value.
	 */
	public void loadAttribute(Component comp, String attr) {
		if (isTemplate(comp) || comp.getPage() == null) {
			return; //skip detached component
		}
		init();
		Binding binding = getBinding(comp, attr);
		if (binding != null) {
			binding.loadAttribute(comp);
		}
	}			

	/** Save value from a specified attribute of the UI component to a data bean property.
	 * @param comp the UI component used to save value into backend data bean.
	 * @param attr the UI component attribute used to save value into backend data bean.
	 */
	public void saveAttribute(Component comp, String attr) {
		if (isTemplate(comp) || comp.getPage() == null) {
			return; //skip detached component
		}
		init();
		Binding binding = getBinding(comp, attr);
		if (binding != null) {
			binding.saveAttribute(comp);
		}
	}
	
	/** Load values from the data bean properties to all attributes of a specified UI component. 
	 * @param comp the UI component to be loaded value.
	 */
	public void loadComponent(Component comp) {
		if (isTemplate(comp) || comp.getPage() == null) {
			return; //skip detached component
		}
		init();
		Collection bindings = getBindings(comp);
		if (bindings != null) {
			loadAttrs(comp, bindings);
		}
			
		//load kids of this component
		for(final Iterator it = comp.getChildren().iterator(); it.hasNext();) {
			loadComponent((Component) it.next()); //recursive
		}
	}
	
	/** Save values from all attributes of a specified UI component to data bean properties.
	 * @param comp the UI component used to save value into backend data bean.
	 */
	public void saveComponent(Component comp) {
		if (isTemplate(comp) || comp.getPage() == null) {
			return; //skip detached component
		}
		init();
		Collection bindings = getBindings(comp);
		if (bindings != null) {
			saveAttrs(comp, bindings);