https://xerces.apache.org/xerces2-j/: Xerces2 is the next generation of high performance, fully compliant XML parsers in the Apache Xerces family. This new version of Xerces introduces the Xerces Native Interface (XNI), a complete framework for building parser components and configurations that is extremely modular and easy to program. The Apache Xerces2 parser is the reference implementation of XNI but other parser components, configurations, and parsers can be written using the Xerces Native Interface. For complete design and implementation documents, refer to the XNI Manual. Xerces2 is a fully conforming XML Schema 1.0 processor. A partial experimental implementation of the XML Schema 1.1 Structures and Datatypes Working Drafts (December 2009) and an experimental implementation of the XML Schema Definition Language (XSD): Component Designators (SCD) Candidate Recommendation (January 2010) are provided for evaluation. For more information, refer to the XML Schema page. Xerces2 also provides a complete implementation of the Document Object Model Level 3 Core and Load/Save W3C Recommendations and provides a complete implementation of the XML Inclusions (XInclude) W3C Recommendation. It also provides support for OASIS XML Catalogs v1.1. Xerces2 is able to parse documents written according to the XML 1.1 Recommendation, except that it does not yet provide an option to enable normalization checking as described in section 2.13 of this specification. It also handles namespaces according to the XML Namespaces 1.1 Recommendation, and will correctly serialize XML 1.1 documents if the DOM level 3 load/save APIs are in use. 
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 * 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
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 *      http://www.apache.org/licenses/LICENSE-2.0
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 * distributed under the License is distributed on an "AS IS" BASIS,
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package org.apache.xerces.xni;

import org.apache.xerces.xni.parser.XMLDocumentSource;


The document handler interface defines callback methods to report
information items in XML documents. Parser components interested in 
document information implement this interface and are registered
as the document handler on the document source.

Author:Andy Clark, IBM
Version:$Id: XMLDocumentHandler.java 447247 2006-09-18 05:23:52Z mrglavas $
/**
 * The document handler interface defines callback methods to report
 * information items in XML documents. Parser components interested in 
 * document information implement this interface and are registered
 * as the document handler on the document source.
 *
 * @author Andy Clark, IBM
 *
 * @version $Id: XMLDocumentHandler.java 447247 2006-09-18 05:23:52Z mrglavas $
 */
public interface XMLDocumentHandler {

    //
    // XMLDocumentHandler methods
    //

    
The start of the document.

Params:
  • locator –  The document locator, or null if the document
                location cannot be reported during the parsing
                of this document. However, it is strongly
                recommended that a locator be supplied that can
                at least report the system identifier of the
                document.
  • encoding – The auto-detected IANA encoding name of the entity
                stream. This value will be null in those situations
                where the entity encoding is not auto-detected (e.g.
                internal entities or a document entity that is
                parsed from a java.io.Reader).
  • namespaceContext – 
                The namespace context in effect at the
                start of this document.
                This object represents the current context.
                Implementors of this class are responsible
                for copying the namespace bindings from the
                the current context (and its parent contexts)
                if that information is important.
  • augs –     Additional information that may include infoset augmentations
Throws:
/**
     * The start of the document.
     * 
     * @param locator  The document locator, or null if the document
     *                 location cannot be reported during the parsing
     *                 of this document. However, it is <em>strongly</em>
     *                 recommended that a locator be supplied that can
     *                 at least report the system identifier of the
     *                 document.
     * @param encoding The auto-detected IANA encoding name of the entity
     *                 stream. This value will be null in those situations
     *                 where the entity encoding is not auto-detected (e.g.
     *                 internal entities or a document entity that is
     *                 parsed from a java.io.Reader).
     * @param namespaceContext
     *                 The namespace context in effect at the
     *                 start of this document.
     *                 This object represents the current context.
     *                 Implementors of this class are responsible
     *                 for copying the namespace bindings from the
     *                 the current context (and its parent contexts)
     *                 if that information is important.
     *                 
     * @param augs     Additional information that may include infoset augmentations
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void startDocument(XMLLocator locator, String encoding, 
                              NamespaceContext namespaceContext,
                              Augmentations augs) 
        throws XNIException;

    
Notifies of the presence of an XMLDecl line in the document. If
present, this method will be called immediately following the
startDocument call.

Params:
  • version –    The XML version.
  • encoding –   The IANA encoding name of the document, or null if
                  not specified.
  • standalone – The standalone value, or null if not specified.
  • augs –       Additional information that may include infoset augmentations
Throws:
/**
     * Notifies of the presence of an XMLDecl line in the document. If
     * present, this method will be called immediately following the
     * startDocument call.
     * 
     * @param version    The XML version.
     * @param encoding   The IANA encoding name of the document, or null if
     *                   not specified.
     * @param standalone The standalone value, or null if not specified.
     * @param augs       Additional information that may include infoset augmentations
     *                   
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void xmlDecl(String version, String encoding, String standalone, Augmentations augs)
        throws XNIException;

    
Notifies of the presence of the DOCTYPE line in the document.

Params:
  • rootElement – 
                The name of the root element.
  • publicId – The public identifier if an external DTD or null
                if the external DTD is specified using SYSTEM.
  • systemId – The system identifier if an external DTD, null
                otherwise.
  • augs –     Additional information that may include infoset augmentations
Throws:
/**
     * Notifies of the presence of the DOCTYPE line in the document.
     * 
     * @param rootElement
     *                 The name of the root element.
     * @param publicId The public identifier if an external DTD or null
     *                 if the external DTD is specified using SYSTEM.
     * @param systemId The system identifier if an external DTD, null
     *                 otherwise.
     * @param augs     Additional information that may include infoset augmentations
     *                 
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void doctypeDecl(String rootElement, String publicId, String systemId, Augmentations augs)
        throws XNIException;

    
A comment.

Params:
  • text –   The text in the comment.
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * A comment.
     * 
     * @param text   The text in the comment.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by application to signal an error.
     */
    public void comment(XMLString text, Augmentations augs) throws XNIException;

    
A processing instruction. Processing instructions consist of a
target name and, optionally, text data. The data is only meaningful
to the application.


Typically, a processing instruction's data will contain a series
of pseudo-attributes. These pseudo-attributes follow the form of
element attributes but are not parsed or presented
to the application as anything other than text. The application is
responsible for parsing the data.

Params:
  • target – The target.
  • data –   The data or null if none specified.
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * A processing instruction. Processing instructions consist of a
     * target name and, optionally, text data. The data is only meaningful
     * to the application.
     * <p>
     * Typically, a processing instruction's data will contain a series
     * of pseudo-attributes. These pseudo-attributes follow the form of
     * element attributes but are <strong>not</strong> parsed or presented
     * to the application as anything other than text. The application is
     * responsible for parsing the data.
     * 
     * @param target The target.
     * @param data   The data or null if none specified.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void processingInstruction(String target, XMLString data, Augmentations augs)
        throws XNIException;

    
The start of an element.

Params:
  • element –    The name of the element.
  • attributes – The element attributes.
  • augs –       Additional information that may include infoset augmentations
Throws:
/**
     * The start of an element.
     * 
     * @param element    The name of the element.
     * @param attributes The element attributes.
     * @param augs       Additional information that may include infoset augmentations
     *                   
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void startElement(QName element, XMLAttributes attributes, Augmentations augs)
        throws XNIException;

    
An empty element.

Params:
  • element –    The name of the element.
  • attributes – The element attributes.
  • augs –       Additional information that may include infoset augmentations
Throws:
/**
     * An empty element.
     * 
     * @param element    The name of the element.
     * @param attributes The element attributes.
     * @param augs       Additional information that may include infoset augmentations
     *                   
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void emptyElement(QName element, XMLAttributes attributes, Augmentations augs)
        throws XNIException;

    
This method notifies the start of a general entity.


Note: This method is not called for entity references
appearing as part of attribute values.

Params:
  • name –     The name of the general entity.
  • identifier – The resource identifier.
  • encoding – The auto-detected IANA encoding name of the entity
                stream. This value will be null in those situations
                where the entity encoding is not auto-detected (e.g.
                internal entities or a document entity that is
                parsed from a java.io.Reader).
  • augs –     Additional information that may include infoset augmentations
Throws:
/**
     * This method notifies the start of a general entity.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param name     The name of the general entity.
     * @param identifier The resource identifier.
     * @param encoding The auto-detected IANA encoding name of the entity
     *                 stream. This value will be null in those situations
     *                 where the entity encoding is not auto-detected (e.g.
     *                 internal entities or a document entity that is
     *                 parsed from a java.io.Reader).
     * @param augs     Additional information that may include infoset augmentations
     *                 
     * @exception XNIException Thrown by handler to signal an error.
     */
    public void startGeneralEntity(String name, 
                                   XMLResourceIdentifier identifier,
                                   String encoding,
                                   Augmentations augs) throws XNIException;

    
Notifies of the presence of a TextDecl line in an entity. If present,
this method will be called immediately following the startEntity call.


Note: This method will never be called for the
document entity; it is only called for external general entities
referenced in document content.


Note: This method is not called for entity references
appearing as part of attribute values.

Params:
  • version –  The XML version, or null if not specified.
  • encoding – The IANA encoding name of the entity.
  • augs –     Additional information that may include infoset augmentations
Throws:
/**
     * Notifies of the presence of a TextDecl line in an entity. If present,
     * this method will be called immediately following the startEntity call.
     * <p>
     * <strong>Note:</strong> This method will never be called for the
     * document entity; it is only called for external general entities
     * referenced in document content.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param version  The XML version, or null if not specified.
     * @param encoding The IANA encoding name of the entity.
     * @param augs     Additional information that may include infoset augmentations
     *                 
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void textDecl(String version, String encoding, Augmentations augs) throws XNIException;

    
This method notifies the end of a general entity.


Note: This method is not called for entity references
appearing as part of attribute values.

Params:
  • name –   The name of the entity.
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * This method notifies the end of a general entity.
     * <p>
     * <strong>Note:</strong> This method is not called for entity references
     * appearing as part of attribute values.
     * 
     * @param name   The name of the entity.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void endGeneralEntity(String name, Augmentations augs) throws XNIException;

    
Character content.

Params:
  • text –   The content.
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * Character content.
     * 
     * @param text   The content.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void characters(XMLString text, Augmentations augs) throws XNIException;

    
Ignorable whitespace. For this method to be called, the document
source must have some way of determining that the text containing
only whitespace characters should be considered ignorable. For
example, the validator can determine if a length of whitespace
characters in the document are ignorable based on the element
content model.

Params:
  • text –   The ignorable whitespace.
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * Ignorable whitespace. For this method to be called, the document
     * source must have some way of determining that the text containing
     * only whitespace characters should be considered ignorable. For
     * example, the validator can determine if a length of whitespace
     * characters in the document are ignorable based on the element
     * content model.
     * 
     * @param text   The ignorable whitespace.
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void ignorableWhitespace(XMLString text, Augmentations augs) throws XNIException;

    
The end of an element.

Params:
  • element – The name of the element.
  • augs –    Additional information that may include infoset augmentations
Throws:
/**
     * The end of an element.
     * 
     * @param element The name of the element.
     * @param augs    Additional information that may include infoset augmentations
     *                
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void endElement(QName element, Augmentations augs) throws XNIException;

    
The start of a CDATA section.

Params:
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * The start of a CDATA section.
     * 
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void startCDATA(Augmentations augs) throws XNIException;

    
The end of a CDATA section.

Params:
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * The end of a CDATA section.
     * 
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void endCDATA(Augmentations augs) throws XNIException;

    
The end of the document.

Params:
  • augs –   Additional information that may include infoset augmentations
Throws:
/**
     * The end of the document.
     * 
     * @param augs   Additional information that may include infoset augmentations
     *               
     * @exception XNIException
     *                   Thrown by handler to signal an error.
     */
    public void endDocument(Augmentations augs) throws XNIException;


    
Sets the document source. 
/** Sets the document source. */
    public void setDocumentSource(XMLDocumentSource source);


    
Returns the document source. 
/** Returns the document source. */
    public XMLDocumentSource getDocumentSource();

} // interface XMLDocumentHandler