/* ErrorMessageConverter.java

	Purpose:
		
	Description:
		
	History:
		2012/2/21 Created by Dennis Chen

Copyright (C) 2011 Potix Corporation. All Rights Reserved.
*/
package org.zkoss.bind.converter.sys;

import org.zkoss.bind.BindContext;
import org.zkoss.bind.Converter;
import org.zkoss.lang.Strings;
import org.zkoss.zk.ui.Component;
import org.zkoss.zk.ui.util.Clients;

/**
 * A internal converter that shows a error message on any component.<br/>
 * @author dennis
 * @since 6.0.1
 */
public class ErrorMessageConverter implements Converter, java.io.Serializable {
	private static final long serialVersionUID = 1L;

	public Object coerceToUi(Object val, Component component, BindContext ctx) {
		final String msg = val == null ? null : val.toString();
		if (Strings.isEmpty(msg)) {
			Clients.clearWrongValue(component);
		} else {
			Clients.wrongValue(component, msg);
		}
		return IGNORED_VALUE;
	}

	public Object coerceToBean(Object val, Component component, BindContext ctx) {
		return val;
	}

}