/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 * 
 *      http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package javax.el;

import java.text.MessageFormat;
import java.util.Iterator;
import java.util.Locale;
import java.util.MissingResourceException;
import java.util.ResourceBundle;

/**
 * @author Jacob Hookom [jacob/hookom.net]
 *
 */
public abstract class ELResolver {
	
	static String message(ELContext context, String name, Object[] props) {
		Locale locale = context.getLocale();
		if (locale == null) {
			locale = Locale.getDefault();
			if (locale == null) {
				return "";
			}
		}
		ResourceBundle bundle = ResourceBundle.getBundle(
				"javax.el.LocalStrings", locale);
		try {
			String template = bundle.getString(name);
			if (props != null) {
				template = MessageFormat.format(template, props);
			}
			return template;
		} catch (MissingResourceException e) {
			return "Missing Resource: '" + name + "' for Locale "
					+ locale.getDisplayName();
		}
	}

    public final static String RESOLVABLE_AT_DESIGN_TIME = "resolvableAtDesignTime";
    
    public final static String TYPE = "type";
    
    public abstract Object getValue(ELContext context, Object base, Object property) throws NullPointerException, PropertyNotFoundException, ELException;
    
    public abstract Class<?> getType(ELContext context, Object base, Object property) throws NullPointerException, PropertyNotFoundException, ELException;
    
    public abstract void setValue(ELContext context, Object base, Object property, Object value) throws NullPointerException, PropertyNotFoundException, PropertyNotWritableException, ELException;

    public abstract boolean isReadOnly(ELContext context, Object base, Object property) throws NullPointerException, PropertyNotFoundException, ELException;
    
    public abstract Iterator<java.beans.FeatureDescriptor> getFeatureDescriptors(ELContext context, Object base);
    
    public abstract Class<?> getCommonPropertyType(ELContext context, Object base);
}