http://xml.apache.org/commons/components/external/: xml-commons provides an Apache-hosted set of DOM, SAX, and JAXP interfaces for use in other xml-based projects. Our hope is that we can standardize on both a common version and packaging scheme for these critical XML standards interfaces to make the lives of both our developers and users easier. The External Components portion of xml-commons contains interfaces that are defined by external standards organizations. For DOM, that's the W3C; for SAX it's David Megginson and sax.sourceforge.net; for JAXP it's Sun. 
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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.
 */
// $Id: TypeInfoProvider.java 884939 2009-11-27 18:20:46Z mrglavas $

package javax.xml.validation;

import org.w3c.dom.TypeInfo;


This class provides access to the type information determined by ValidatorHandler. 

Some schema languages, such as W3C XML Schema, encourages a validator
to report the "type" it assigns to each attribute/element.
Those applications who wish to access this type information can invoke
methods defined on this "interface" to access such type information.
 

 Implementation of this "interface" can be obtained through the ValidatorHandler.getTypeInfoProvider() method. 
Author: Kohsuke Kawaguchi
See Also:
Version:$Revision: 884939 $, $Date: 2009-11-27 13:20:46 -0500 (Fri, 27 Nov 2009) $
Since:1.5
/**
 * This class provides access to the type information determined
 * by {@link ValidatorHandler}. 
 * 
 * <p>
 * Some schema languages, such as W3C XML Schema, encourages a validator
 * to report the "type" it assigns to each attribute/element.
 * Those applications who wish to access this type information can invoke
 * methods defined on this "interface" to access such type information.
 *  
 * <p>
 * Implementation of this "interface" can be obtained through the
 * {@link ValidatorHandler#getTypeInfoProvider()} method.
 * 
 * @author  <a href="mailto:Kohsuke.Kawaguchi@Sun.com">Kohsuke Kawaguchi</a>
 * @version $Revision: 884939 $, $Date: 2009-11-27 13:20:46 -0500 (Fri, 27 Nov 2009) $
 * @see org.w3c.dom.TypeInfo 
 * @since 1.5
 */
public abstract class TypeInfoProvider {
    
    
Constructor for the derived class.


The constructor does nothing.

/**
     * Constructor for the derived class.
     * 
     * <p>
     * The constructor does nothing.
     */
    protected TypeInfoProvider() {
    }
    
    
Returns the immutable TypeInfo object for the current element.


 The method may only be called by the startElement and endElement event of the ContentHandler that the application sets to the ValidatorHandler.


Throws:
Returns: An immutable TypeInfo object that represents the type of the current element. Note that the caller can keep references to the obtained TypeInfo longer than the callback scope. Otherwise, this method returns null if the validator is unable to determine the type of the current element for some reason (for example, if the validator is recovering from an earlier error.)
/**
     * <p>Returns the immutable {@link TypeInfo} object for the current element.</p>
     * 
     * <p>
     * The method may only be called by the startElement and endElement event of
     * the {@link org.xml.sax.ContentHandler} that the application sets to the
     * {@link ValidatorHandler}.</p>
     * 
     * @throws IllegalStateException
     *      If this method is called from other {@link org.xml.sax.ContentHandler}
     *      methods.
     * @return

     *      An immutable {@link TypeInfo} object that represents the
     *      type of the current element. 
     *      Note that the caller can keep references to the obtained
     *      {@link TypeInfo} longer than the callback scope.
     * 
     *      Otherwise, this method returns
     *      null if the validator is unable to
     *      determine the type of the current element for some reason
     *      (for example, if the validator is recovering from
     *      an earlier error.)
     * 
     */
    public abstract TypeInfo getElementTypeInfo();
    
    
Returns the immutable TypeInfo object for the specified attribute of the current element. 
 The method may only be called by the startElement event of the ContentHandler that the application sets to the ValidatorHandler. 
Params:
  • index –  The index of the attribute. The same index for the Attributes object passed to the startElement callback.
Throws:
Returns: An immutable TypeInfo object that represents the type of the specified attribute. Note that the caller can keep references to the obtained TypeInfo longer than the callback scope. Otherwise, this method returns null if the validator is unable to determine the type.
/**
     * Returns the immutable {@link TypeInfo} object for the specified
     * attribute of the current element.
     * 
     * <p>
     * The method may only be called by the startElement event of
     * the {@link org.xml.sax.ContentHandler} that the application sets to the
     * {@link ValidatorHandler}.
     * 
     * @param index
     *      The index of the attribute. The same index for
     *      the {@link org.xml.sax.Attributes} object passed to the
     *      <tt>startElement</tt> callback.
     * 
     * @throws IndexOutOfBoundsException
     *      If the index is invalid.
     * @throws IllegalStateException
     *      If this method is called from other {@link org.xml.sax.ContentHandler}
     *      methods.
     * 
     * @return

     *      An immutable {@link TypeInfo} object that represents the
     *      type of the specified attribute. 
     *      Note that the caller can keep references to the obtained
     *      {@link TypeInfo} longer than the callback scope.
     * 
     *      Otherwise, this method returns
     *      null if the validator is unable to
     *      determine the type.
     */
    public abstract TypeInfo getAttributeTypeInfo(int index);
    
    
Returns true if the specified attribute is determined
to be ID.


Exactly how an attribute is "determined to be ID" is up to the
schema language. In case of W3C XML Schema, this means
that the actual type of the attribute is the built-in ID type
or its derived type.

 A DocumentBuilder uses this information to properly implement Attr.isId(). 
 The method may only be called by the startElement event of the ContentHandler that the application sets to the ValidatorHandler. 
Params:
  • index –  The index of the attribute. The same index for the Attributes object passed to the startElement callback.
Throws:
Returns:true
     if the type of the specified attribute is ID.
/**
     * Returns <tt>true</tt> if the specified attribute is determined
     * to be ID.
     * 
     * <p>
     * Exactly how an attribute is "determined to be ID" is up to the
     * schema language. In case of W3C XML Schema, this means
     * that the actual type of the attribute is the built-in ID type
     * or its derived type.
     * 
     * <p>
     * A {@link javax.xml.parsers.DocumentBuilder} uses this information
     * to properly implement {@link org.w3c.dom.Attr#isId()}.
     * 
     * <p>
     * The method may only be called by the startElement event of
     * the {@link org.xml.sax.ContentHandler} that the application sets to the
     * {@link ValidatorHandler}.
     * 
     * @param index
     *      The index of the attribute. The same index for
     *      the {@link org.xml.sax.Attributes} object passed to the
     *      <tt>startElement</tt> callback.
     * 
     * @throws IndexOutOfBoundsException
     *      If the index is invalid.
     * @throws IllegalStateException
     *      If this method is called from other {@link org.xml.sax.ContentHandler}
     *      methods.
     * 
     * @return true
     *      if the type of the specified attribute is ID.
     */
    public abstract boolean isIdAttribute(int index);
    
    
Returns false if the attribute was added by the validator.

 This method provides information necessary for a DocumentBuilder to determine what the DOM tree should return from the Attr.getSpecified() method. 
 The method may only be called by the startElement event of the ContentHandler that the application sets to the ValidatorHandler. 

A general guideline for validators is to return true if
the attribute was originally present in the pipeline, and
false if it was added by the validator.

Params:
  • index –  The index of the attribute. The same index for the Attributes object passed to the startElement callback.
Throws:
Returns:
     true if the attribute was present before the validator
     processes input. false if the attribute was added
     by the validator.
/**
     * Returns <tt>false</tt> if the attribute was added by the validator.
     * 
     * <p>
     * This method provides information necessary for
     * a {@link javax.xml.parsers.DocumentBuilder} to determine what
     * the DOM tree should return from the {@link org.w3c.dom.Attr#getSpecified()} method.
     * 
     * <p>
     * The method may only be called by the startElement event of
     * the {@link org.xml.sax.ContentHandler} that the application sets to the
     * {@link ValidatorHandler}.
     * 
     * <p>
     * A general guideline for validators is to return true if
     * the attribute was originally present in the pipeline, and
     * false if it was added by the validator.
     * 
     * @param index
     *      The index of the attribute. The same index for
     *      the {@link org.xml.sax.Attributes} object passed to the
     *      <tt>startElement</tt> callback.
     * 
     * @throws IndexOutOfBoundsException
     *      If the index is invalid.
     * @throws IllegalStateException
     *      If this method is called from other {@link org.xml.sax.ContentHandler}
     *      methods.
     * 
     * @return

     *      <tt>true</tt> if the attribute was present before the validator
     *      processes input. <tt>false</tt> if the attribute was added
     *      by the validator.
     */
    public abstract boolean isSpecified(int index);
}