databinder.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

/* DataBinder.java

{{IS_NOTE
	Purpose:
		
	Description:
		
	History:
		Wed Nov 15 14:24:25     2006, Created by Henri Chen.
}}IS_NOTE

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

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

import org.zkoss.zk.ui.Path;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.UiException;
import org.zkoss.zk.ui.WrongValueException;
import org.zkoss.zk.ui.event.Event;
import org.zkoss.zk.ui.event.Express;
import org.zkoss.zk.ui.event.EventListener;
import org.zkoss.zk.ui.sys.ComponentCtrl;
import org.zkoss.zk.ui.metainfo.Annotation; 

import org.zkoss.zul.impl.InputElement;
import org.zkoss.zul.Listbox;
import org.zkoss.zul.Listitem;
import org.zkoss.zul.ListModel;
import org.zkoss.zul.Checkbox;
import org.zkoss.zul.Slider;
import org.zkoss.zul.Calendar;
import org.zkoss.zul.ListitemRenderer;

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

import java.util.Map;
import java.util.Set;
import java.util.List;
import java.util.HashSet;
import java.util.HashMap;
import java.util.Iterator;
import java.util.ArrayList;
import java.util.Collection;
import java.util.LinkedHashSet;
import java.util.LinkedHashMap;
import java.lang.reflect.Method;

/**
 * The DataBinder used for binding ZK UI component and the backend data bean.
 *
 * @author Henri Chen
 */
public class DataBinder {
	private Map _compBindingMap = new LinkedHashMap(29); //(comp, Map(attr, Binding))
	private Map _beanBindingMap = new HashMap(29); //(beanid, Set(Binding))
	private Map _sameBeanidMap = new HashMap(5); //(bean, Set(beanid)) and (beanid, Set(beanid));
	private Map _cloneMap = new HashMap(255); //(cloned item target, Map(template, clone))
	private Map _beans = new HashMap(5); //(beanid, bean)
//	private Node _dependency = new Node(); //(beanid+prop) dependency tree.
	
	private boolean _init; //whether this databinder is initialized. 
							//Databinder is init automatically when saveXXX or loadXxx is called
	private static Map _converterMap = new HashMap(5); //(converterClassName, converter)
	private static final String VAR = "org.koss.zkplus.databind.VAR"; //the template variable name
	private static final String INDEXITEM = "org.koss.zkplus.databind.INDEXITEM"; //the listitem with index
	private static final String TEMPLATE = "org.koss.zkplus.databind.TEMPLATE"; //the template
	private static final String ISTEMPLATE = "org.koss.zkplus.databind.ISTEMPLATE"; //whether a template
	private static final Object NA = new Object();
	
	/** Binding bean to UI component. This is the same as addBinding(comp, attr, value, null, null). 
	 * @param comp The component to be associated.
	 * @param attr The attribute of the component to be associated.
	 * @param value The expression to associate the data bean.
	 */
	public void addBinding(Component comp, String attr, String value) {
		addBinding(comp, attr, value, null, 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 value 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 value,
		String[] loadWhenEvents, String saveWhenEvent, String access, String converter) {
			
		//handle default-bind defined in lang-addon.xml
		Object[] objs = loadPropertyAnnotation(comp, attr, "default-bind");
		/* logically impossible to hold "value" in default binding 
		if (value == null) {
			value = (String) objs[0];
		}
		if (loadWhenEvents == null) {
			loadWhenEvents = (String[]) objs[1];
		}
		*/
		if (saveWhenEvent == null) {
			saveWhenEvent = (String) objs[2];
		}
		if (access == null) {
			access = (String) objs[3];
		}
		if (converter == null) {
			converter = (String) objs[4];
		}
		Map attrMap = (Map) _compBindingMap.get(comp);
		if (attrMap == null) {
			attrMap = new LinkedHashMap(3);
			_compBindingMap.put(comp, attrMap);
		}
		if (attrMap.containsKey(attr)) { //override and merge
			final Binding binding = (Binding) attrMap.get(attr);
			binding.setValue(value);
			binding.addLoadWhenEvents(loadWhenEvents);
			binding.setSaveWhenEvent(saveWhenEvent);
			binding.setAccess(access);
			binding.setConverter(converter);
		} else {
			if (objs[1] != null) { //default-bind
				loadWhenEvents = mergeStringArray((String[])objs[1], loadWhenEvents);
			}
			attrMap.put(attr, new Binding(comp, attr, value, loadWhenEvents, saveWhenEvent, 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);
		}
	}

	//[0] value, [1] loadWhenEvents, [2] saveWhenEvent, [3] access, [4] converter
	protected Object[] loadPropertyAnnotation(Component comp, String propName, String bindName) {
		ComponentCtrl compCtrl = (ComponentCtrl) comp;
		Annotation ann = compCtrl.getAnnotation(propName, bindName);
		if (ann != null) {
			final Map attrs = ann.getAttributes(); //(tag, tagExpr)
			String[] loadWhenEvents = null;
			String saveWhenEvent = null;
			String access = null;
			String converter = null;
			String expr = null;
			for (final Iterator it = attrs.entrySet().iterator(); it.hasNext();) {
				Map.Entry entry = (Map.Entry) it.next();
				String tag = (String) entry.getKey();
				String tagExpr = (String) entry.getValue();
	
				if ("save-when".equals(tag)) {
					saveWhenEvent = tagExpr;
				} else if ("access".equals(tag)) {
					access = tagExpr;
				} else if ("converter".equals(tag)) {
					converter = tagExpr;
				} else if ("load-when".equals(tag)) {
					loadWhenEvents = parseExpression(tagExpr, ",");
				} else if ("value".equals(tag)) {
					expr = tagExpr;
				}
			}
			return new Object[] {expr, loadWhenEvents, saveWhenEvent, access, converter};
		}
		return new Object[5];
	}
	
	/** 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) {
		//skip detached component
		if (comp.getPage() != null) {
			init();
			final Component template = getTemplateComponent(comp);
			Map attrMap = (Map) (template != null ? _compBindingMap.get(template) : _compBindingMap.get(comp));
			if (attrMap != null) {
				Binding binding = (Binding) attrMap.get(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) {
		//skip detached component
		if (comp.getPage() != null) {
			init();
			final Component template = getTemplateComponent(comp);
			Map attrMap = (Map) (template != null ? _compBindingMap.get(template) : _compBindingMap.get(comp));
			if (attrMap != null) {
				Binding binding = (Binding) attrMap.get(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) {
		//skip detached component
		if (comp.getPage() != null) {
			init();
			final Component template = getTemplateComponent(comp);
			Map attrMap = (Map) (template != null ? _compBindingMap.get(template) : _compBindingMap.get(comp));
			if (attrMap != null) {
				loadAttrs(comp, attrMap.values());
			}
			
			//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) {
		//skip detached component
		if (comp.getPage() != null) {
			init();
			final Component template = getTemplateComponent(comp);
			Map attrMap = (Map) (template != null ? _compBindingMap.get(template) : _compBindingMap.get(comp));
			if (attrMap != null) {
				saveAttrs(comp, attrMap.values());
			}

			//save kids of this component
			for(final Iterator it = comp.getChildren().iterator(); it.hasNext();) {
				saveComponent((Component) it.next()); //recursive
			}
		}
	}
	
	/** Load all value from data beans to UI components. */
	public void loadAll() {
		init();
		for (final Iterator it = _compBindingMap.keySet().iterator(); it.hasNext(); ) {
			final Component comp = (Component) it.next();
			if (isTemplate(comp)) { //do via model and renderer, so skip
				continue;
			}
			loadComponent(comp);
		}
	}
	
	/** Save all values from UI components to beans. */
	public void saveAll() {
		init();
		for (final Iterator it = _compBindingMap.keySet().iterator(); it.hasNext(); ) {
			final Component comp = (Component) it.next();
			if (isTemplate(comp)) { //do via model and renderer, so skip
				continue;
			}
			saveComponent(comp);
		}
	}

	private void loadAttrs(Component comp, Collection attrs) {
		for(final Iterator it = attrs.iterator(); it.hasNext();) {
			Binding binding = (Binding) it.next();
			binding.loadAttribute(comp);
		}
	}	

	private void saveAttrs(Component comp, Collection attrs) {
		for(final Iterator it = attrs.iterator(); it.hasNext();) {
			Binding binding = (Binding) it.next();
			binding.saveAttribute(comp);
		}
	}

	//late init
	protected void init() {
		if (!_init) {
			_init = true;
			
			//process template data binding
			List detachs = new ArrayList(_compBindingMap.size());
			for(final Iterator it = _compBindingMap.keySet().iterator(); it.hasNext();) {
				final Component comp = (Component) it.next();
				final Map attrMap = (Map) _compBindingMap.get(comp);
				
				//_var special case; meaning a template component
				if (attrMap.containsKey("_var")) {
					comp.setAttribute(VAR, ((Binding)attrMap.get("_var")).getBeanid());
					setupTemplate(comp, Boolean.TRUE);
					setupRenderer(comp);
					detachs.add(comp);
				}

				//register event handler
				registerEvents(comp, attrMap.values());
				
				//register beanid -> Binding(s) map
				registerBeanidBinding(comp, attrMap.values());
			}
			
			for(final Iterator it = detachs.iterator(); it.hasNext(); ) {
				final Component comp = (Component) it.next();
				comp.detach();
			}
		}
	}
	
	private void registerEvents(Component comp, Collection attrs) {
		for(final Iterator it = attrs.iterator(); it.hasNext();) {