alvinalexander.com | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (StAXStream2SAX.java)

This example Java source code file (StAXStream2SAX.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

attributes, contenthandler, ioexception, lexicalhandler, nullpointerexception, object, qname, sax, saxexception, saximpl, saxnotrecognizedexception, saxnotsupportedexception, staxstream2sax, string, util, xmlstreamexception

The StAXStream2SAX.java Java example source code

/*
 * Copyright (c) 2005, 2006, Oracle and/or its affiliates. All rights reserved.
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
 *
 * This code is free software; you can redistribute it and/or modify it
 * under the terms of the GNU General Public License version 2 only, as
 * published by the Free Software Foundation.  Oracle designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Oracle in the LICENSE file that accompanied this code.
 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
 *
 * You should have received a copy of the GNU General Public License version
 * 2 along with this work; if not, write to the Free Software Foundation,
 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
 *
 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
 * or visit www.oracle.com if you need additional information or have any
 * questions.
 */

package com.sun.org.apache.xalan.internal.xsltc.trax;

import java.io.IOException;
import java.util.Hashtable;
import java.util.Stack;
import java.util.Vector;
import java.util.Iterator;

import org.xml.sax.Attributes;
import org.xml.sax.ContentHandler;
import org.xml.sax.DTDHandler;
import org.xml.sax.EntityResolver;
import org.xml.sax.ErrorHandler;
import org.xml.sax.InputSource;
import org.xml.sax.Locator;
import org.xml.sax.SAXException;
import org.xml.sax.SAXNotRecognizedException;
import org.xml.sax.SAXNotSupportedException;
import org.xml.sax.XMLReader;
import org.xml.sax.ext.LexicalHandler;
import org.xml.sax.ext.Locator2;
import org.xml.sax.helpers.AttributesImpl;
import com.sun.org.apache.xalan.internal.xsltc.dom.SAXImpl;



import javax.xml.namespace.QName;
import javax.xml.stream.XMLStreamReader;
import javax.xml.stream.XMLStreamConstants;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.events.Attribute;
import javax.xml.stream.events.Characters;
import javax.xml.stream.events.EndElement;
import javax.xml.stream.events.Namespace;
import javax.xml.stream.events.ProcessingInstruction;
import javax.xml.stream.events.StartElement;
import javax.xml.stream.events.StartDocument;
import javax.xml.stream.events.XMLEvent;



/**
 * @author Padmaja Vedula
 * @author Sunitha Reddy
 */
public class StAXStream2SAX implements XMLReader, Locator {

    //private final static String EMPTYSTRING = "";
    //private static final String XMLNS_PREFIX = "xmlns";

    // StAX Stream source
    private final XMLStreamReader staxStreamReader;

    //private Node _dom = null;
    private ContentHandler _sax = null;
    private LexicalHandler _lex = null;
    private SAXImpl _saxImpl = null;
    //private Hashtable _nsPrefixes = new Hashtable();

    public StAXStream2SAX(XMLStreamReader staxSrc) {
            staxStreamReader = staxSrc;
    }

    public ContentHandler getContentHandler() {
        return _sax;
    }

    public void setContentHandler(ContentHandler handler) throws
        NullPointerException
    {
        _sax = handler;
        if (handler instanceof LexicalHandler) {
            _lex = (LexicalHandler) handler;
        }

        if (handler instanceof SAXImpl) {
            _saxImpl = (SAXImpl)handler;
        }
    }


    public void parse(InputSource unused) throws IOException, SAXException {
        try {
            bridge();
        } catch (XMLStreamException e) {
            throw new SAXException(e);
        }
    }


    //Main Work Starts Here.
    public void parse() throws IOException, SAXException, XMLStreamException {
        bridge();
    }


   /**
     * This class is only used internally so this method should never
     * be called.
     */
    public void parse(String sysId) throws IOException, SAXException {
        throw new IOException("This method is not yet implemented.");
    }


   public void bridge() throws XMLStreamException {

        try {
            // remembers the nest level of elements to know when we are done.
            int depth=0;

            // skip over START_DOCUMENT
            int event = staxStreamReader.getEventType();
            if (event == XMLStreamConstants.START_DOCUMENT) {
                event = staxStreamReader.next();
            }

            // If not a START_ELEMENT (e.g., a DTD), skip to next tag
            if (event != XMLStreamConstants.START_ELEMENT) {
                event = staxStreamReader.nextTag();
                // An error if a START_ELEMENT isn't found now
                if (event != XMLStreamConstants.START_ELEMENT) {
                    throw new IllegalStateException("The current event is " +
                            "not START_ELEMENT\n but" + event);
                }
            }

            handleStartDocument();

            do {
                // These are all of the events listed in the javadoc for
                // XMLEvent.
                // The spec only really describes 11 of them.
                switch (event) {
                    case XMLStreamConstants.START_ELEMENT :
                        depth++;
                        handleStartElement();
                        break;
                    case XMLStreamConstants.END_ELEMENT :
                        handleEndElement();
                        depth--;
                        break;
                    case XMLStreamConstants.CHARACTERS :
                        handleCharacters();
                        break;
                    case XMLStreamConstants.ENTITY_REFERENCE :
                        handleEntityReference();
                        break;
                    case XMLStreamConstants.PROCESSING_INSTRUCTION :
                        handlePI();
                        break;
                    case XMLStreamConstants.COMMENT :
                        handleComment();
                        break;
                    case XMLStreamConstants.DTD :
                        handleDTD();
                        break;
                    case XMLStreamConstants.ATTRIBUTE :
                        handleAttribute();
                        break;
                    case XMLStreamConstants.NAMESPACE :
                        handleNamespace();
                        break;
                    case XMLStreamConstants.CDATA :
                        handleCDATA();
                        break;
                    case XMLStreamConstants.ENTITY_DECLARATION :
                        handleEntityDecl();
                        break;
                    case XMLStreamConstants.NOTATION_DECLARATION :
                        handleNotationDecl();
                        break;
                    case XMLStreamConstants.SPACE :
                        handleSpace();
                        break;
                    default :
                        throw new InternalError("processing event: " + event);
                }

                event=staxStreamReader.next();
            } while (depth!=0);

            handleEndDocument();
        } catch (SAXException e) {
            throw new XMLStreamException(e);
        }
    }

    private void handleEndDocument() throws SAXException {
        _sax.endDocument();
    }

    private void handleStartDocument() throws SAXException {
        _sax.setDocumentLocator(new Locator2() {
            public int getColumnNumber() {
                return staxStreamReader.getLocation().getColumnNumber();
            }
            public int getLineNumber() {
                return staxStreamReader.getLocation().getLineNumber();
            }
            public String getPublicId() {
                return staxStreamReader.getLocation().getPublicId();
            }
            public String getSystemId() {
                return staxStreamReader.getLocation().getSystemId();
            }
            public String getXMLVersion() {
                return staxStreamReader.getVersion();
            }
            public String getEncoding() {
                return staxStreamReader.getEncoding();
            }
         });
        _sax.startDocument();
    }

    private void handlePI() throws XMLStreamException {
        try {
            _sax.processingInstruction(
                staxStreamReader.getPITarget(),
                staxStreamReader.getPIData());
        } catch (SAXException e) {
            throw new XMLStreamException(e);
        }
    }

    private void handleCharacters() throws XMLStreamException {

        // workaround for bugid 5046319 - switch over to commented section
        // below when it is fixed.
        int textLength = staxStreamReader.getTextLength();
        char[] chars = new char[textLength];

        staxStreamReader.getTextCharacters(0, chars, 0, textLength);

        try {
            _sax.characters(chars, 0, chars.length);
        } catch (SAXException e) {
            throw new XMLStreamException(e);
        }


//        int start = 0;
//        int len;
//        do {
//            len = staxStreamReader.getTextCharacters(start, buf, 0, buf.length);
//            start += len;
//            try {
//                _sax.characters(buf, 0, len);
//            } catch (SAXException e) {
//                throw new XMLStreamException(e);
//            }
//        } while (len == buf.length);
    }

    private void handleEndElement() throws XMLStreamException {
        QName qName = staxStreamReader.getName();

        try {
            //construct prefix:localName from qName
            String qname = "";
            if (qName.getPrefix() != null && qName.getPrefix().trim().length() != 0){
                qname = qName.getPrefix() + ":";
            }
            qname += qName.getLocalPart();

            // fire endElement
            _sax.endElement(
                qName.getNamespaceURI(),
                qName.getLocalPart(),
                qname);

            // end namespace bindings
            int nsCount = staxStreamReader.getNamespaceCount();
            for (int i = nsCount - 1; i >= 0; i--) {
                String prefix = staxStreamReader.getNamespacePrefix(i);
                if (prefix == null) { // true for default namespace
                    prefix = "";
                }
                _sax.endPrefixMapping(prefix);
            }
        } catch (SAXException e) {
            throw new XMLStreamException(e);
        }
    }

    private void handleStartElement() throws XMLStreamException {

        try {
            // start namespace bindings
            int nsCount = staxStreamReader.getNamespaceCount();
            for (int i = 0; i < nsCount; i++) {
                String prefix = staxStreamReader.getNamespacePrefix(i);
                if (prefix == null) { // true for default namespace
                    prefix = "";
                }
                _sax.startPrefixMapping(
                    prefix,
                    staxStreamReader.getNamespaceURI(i));
            }

            // fire startElement
            QName qName = staxStreamReader.getName();
            String prefix = qName.getPrefix();
            String rawname;
            if(prefix==null || prefix.length()==0)
                rawname = qName.getLocalPart();
            else
                rawname = prefix + ':' + qName.getLocalPart();
            Attributes attrs = getAttributes();
            _sax.startElement(
                qName.getNamespaceURI(),
                qName.getLocalPart(),
                rawname,
                attrs);
        } catch (SAXException e) {
            throw new XMLStreamException(e);
        }
    }

    /**
     * Get the attributes associated with the given START_ELEMENT or ATTRIBUTE
     * StAXevent.
     *
     * @return the StAX attributes converted to an org.xml.sax.Attributes
     */
    private Attributes getAttributes() {
        AttributesImpl attrs = new AttributesImpl();

        int eventType = staxStreamReader.getEventType();
        if (eventType != XMLStreamConstants.ATTRIBUTE
            && eventType != XMLStreamConstants.START_ELEMENT) {
            throw new InternalError(
                "getAttributes() attempting to process: " + eventType);
        }

        // in SAX, namespace declarations are not part of attributes by default.
        // (there's a property to control that, but as far as we are concerned
        // we don't use it.) So don't add xmlns:* to attributes.

        // gather non-namespace attrs
        for (int i = 0; i < staxStreamReader.getAttributeCount(); i++) {
            String uri = staxStreamReader.getAttributeNamespace(i);
            if(uri==null)   uri="";
            String localName = staxStreamReader.getAttributeLocalName(i);
            String prefix = staxStreamReader.getAttributePrefix(i);
            String qName;
            if(prefix==null || prefix.length()==0)
                qName = localName;
            else
                qName = prefix + ':' + localName;
            String type = staxStreamReader.getAttributeType(i);
            String value = staxStreamReader.getAttributeValue(i);

            attrs.addAttribute(uri, localName, qName, type, value);
        }

        return attrs;
    }

    private void handleNamespace() {
        // no-op ???
        // namespace events don't normally occur outside of a startElement
        // or endElement
    }

    private void handleAttribute() {
        // no-op ???
        // attribute events don't normally occur outside of a startElement
        // or endElement
    }

    private void handleDTD() {
        // no-op ???
        // it seems like we need to pass this info along, but how?
    }

    private void handleComment() {
        // no-op ???
    }

    private void handleEntityReference() {
        // no-op ???
    }

    private void handleSpace() {
        // no-op ???
        // this event is listed in the javadoc, but not in the spec.
    }

    private void handleNotationDecl() {
        // no-op ???
        // this event is listed in the javadoc, but not in the spec.
    }

    private void handleEntityDecl() {
        // no-op ???
        // this event is listed in the javadoc, but not in the spec.
    }

    private void handleCDATA() {
        // no-op ???
        // this event is listed in the javadoc, but not in the spec.
    }


    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public DTDHandler getDTDHandler() {
        return null;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public ErrorHandler getErrorHandler() {
        return null;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public boolean getFeature(String name) throws SAXNotRecognizedException,
        SAXNotSupportedException
    {
        return false;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public void setFeature(String name, boolean value) throws
        SAXNotRecognizedException, SAXNotSupportedException
    {
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public void setDTDHandler(DTDHandler handler) throws NullPointerException {
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public void setEntityResolver(EntityResolver resolver) throws
        NullPointerException
    {
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public EntityResolver getEntityResolver() {
        return null;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public void setErrorHandler(ErrorHandler handler) throws
        NullPointerException
    {
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public void setProperty(String name, Object value) throws
        SAXNotRecognizedException, SAXNotSupportedException {
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public Object getProperty(String name) throws SAXNotRecognizedException,
        SAXNotSupportedException
    {
        return null;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public int getColumnNumber() {
        return 0;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public int getLineNumber() {
        return 0;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public String getPublicId() {
        return null;
    }

    /**
     * This class is only used internally so this method should never
     * be called.
     */
    public String getSystemId() {
        return null;
    }

}

Other Java examples (source code examples)

Here is a short list of links related to this Java StAXStream2SAX.java source code file:

... this post is sponsored by my books ...

#1 New Release!

FP Best Seller

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.