/*
 * 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 org.apache.xerces.xs;

/**
 * This interface provides access to the post schema validation infoset for an 
 * API that provides a streaming document infoset, such as SAX, XNI, and 
 * others. 
 * <p>For implementations that would like to provide access to the PSVI in a 
 * streaming model, a parser object should also implement the 
 * <code>PSVIProvider</code> interface. Within the scope of the methods 
 * handling the start and end of an element, applications may use the 
 * <code>PSVIProvider</code> to retrieve the PSVI related to the element and 
 * its attributes.
 */
public interface PSVIProvider {
    /**
     *  Provides the post schema validation item for the current element 
     * information item. The method must be called by an application while 
     * in the scope of the methods which report the start and end of an 
     * element. For example, for SAX the method must be called within the 
     * scope of the document handler's <code>startElement</code> or 
     * <code>endElement</code> call. If the method is called outside of the 
     * specified scope, the return value is undefined. 
     * @return The post schema validation infoset for the current element. If 
     *   an element information item is valid, then in the 
     *   post-schema-validation infoset the following properties must be 
     *   available for the element information item: The following 
     *   properties are available in the scope of the method that reports 
     *   the start of an element: {element declaration}, {validation 
     *   context}, {notation}. The {schema information} property is 
     *   available for the validation root. The {error codes} property is 
     *   available if any errors occured during validation.  The following 
     *   properties are available in the scope of the method that reports 
     *   the end of an element: {nil}, {schema specified}, {normalized 
     *   value},{ member type definition}, {validity}, {validation attempted}
     *   . If the declaration has a value constraint, the property {schema 
     *   default} is available. The {error codes} property is available if 
     *   any errors occured during validation. Note: some processors may 
     *   choose to provide all the PSVI properties in the scope of the 
     *   method that reports the end of an element. 
     */
    public ElementPSVI getElementPSVI();

    /**
     * Provides <code>AttributePSVI</code> given the index of an attribute 
     * information item in the current element's attribute list. The method 
     * must be called by an application while in the scope of the methods 
     * which report the start and end of an element at a point where the 
     * attribute list is available. For example, for SAX the method must be 
     * called while in the scope of the document handler's 
     * <code>startElement</code> call. If the method is called outside of 
     * the specified scope, the return value is undefined.
     * @param index The attribute index. 
     * @return The post schema validation properties of the attribute.
     */
    public AttributePSVI getAttributePSVI(int index);

    /**
     * Provides <code>AttributePSVI</code> given the namespace name and the 
     * local name of an attribute information item in the current element's 
     * attribute list. The method must be called by an application while in 
     * the scope of the methods which report the start and end of an element 
     * at a point where the attribute list is available. For example, for 
     * SAX the method must be called while in the scope of the document 
     * handler's <code>startElement</code> call. If the method is called 
     * outside of the specified scope, the return value is undefined.
     * @param uri The namespace name of an attribute. 
     * @param localname The local name of an attribute. 
     * @return The post schema validation properties of the attribute.
     */
    public AttributePSVI getAttributePSVIByName(String uri, 
                                                String localname);

}