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/*
 * 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.faces.component;

/**
 * Interface implemented by components that provide a new "namespace" for the ids of their
 * child components.
 * 
 * Component ids must be unique between all descendants of a NamingContainer; the JSF library
 * will report a fatal error and refuse to process or render any view where two components
 * in the same NamingContainer have identical id values. However a component that is a descendant
 * of one NamingContainer component is permitted to have the same id as a component that is a
 * descendant of a different NamingContainer component.
 * 

 * Unique component ids are used to:
 * 

 * generate unique names for HTML form fields, etc
 * search for components via UIComponent.findComponent(String expr)
 * on re-render after postback, match up component declarations in the view templates
 * with existing components in the restored view tree.
 * 
 * 
 * Requiring every component in a large view (which is possibly built by including or
 * composing multiple files together) to have an id which is different from every other id
 * is simply unmanageable; JSF certainly must provide some kind of id namespacing.
 * Therefore this base class is defined, and a few standard JSF components subclass it
 * (in particular, f:subview).
 * 

 * When generating clientId values during rendering, descendants of a NamingContainer instance
 * are allocated a clientId which is their own id prefixed with the clientId of the ancestor
 * NamingContainer, eg "parentId:childId". NamingContainer components can be nested within
 * other NamingContainer components, generating clientIds like "firstId:middleId:leafId". 
 * 

 * Not every component is a naming container; that would technically work, but the clientId
 * values generated would quickly grow excessively long.
 * 
 * See the javadoc for this class in the 
 * JSF Specification
 * for further details.
 *
 * @author Manfred Geiler (latest modification by $Author: bommel $)
 * @version $Revision: 1187700 $ $Date: 2011-10-22 07:19:37 -0500 (Sat, 22 Oct 2011) $
 */
public interface NamingContainer
{
    /**
     * @deprecated Use {@link UINamingContainer#getSeparatorChar(javax.faces.context.FacesContext)
     */
    public static final char SEPARATOR_CHAR = ':';
}