XMLUtils.java

/*
 * GovWay - A customizable API Gateway 
 * https://govway.org
 * 
 * Copyright (c) 2005-2025 Link.it srl (https://link.it). 
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License version 3, as published by
 * the Free Software Foundation.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

package org.openspcoop2.utils.xml;

import javax.xml.XMLConstants;
import javax.xml.datatype.DatatypeFactory;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.TransformerFactory;
import javax.xml.validation.SchemaFactory;
import javax.xml.xpath.XPathFactory;

/** 
 * XMLUtils
 *
 * @author Poli Andrea (apoli@link.it)
 * @author $Author$
 * @version $Rev$, $Date$
 */
public class XMLUtils extends AbstractXMLUtils {

    protected XMLUtils() {}
    
    private static XMLUtils xmlUtils = null;
    private static synchronized void init(){
        if(XMLUtils.xmlUtils==null){
            XMLUtils.xmlUtils = new XMLUtils();
        }
    }
    public static XMLUtils getInstance(){
        if(XMLUtils.xmlUtils==null){
            // spotbugs warning 'SING_SINGLETON_GETTER_NOT_SYNCHRONIZED'
            synchronized (XMLUtils.class) {
                XMLUtils.init();
            }
        }
        return XMLUtils.xmlUtils;
    }
    
    // XERCES
    @Override
    protected DocumentBuilderFactory newDocumentBuilderFactory() throws XMLException{
        try{
            // force xerces impl
            /**System.setProperty("javax.xml.parsers.DocumentBuilderFactory", org.apache.xerces.jaxp.DocumentBuilderFactoryImpl.class.getName());
            return DocumentBuilderFactory.newInstance();*/
            DocumentBuilderFactory documentBuilderFactory = DocumentBuilderFactory.newInstance(org.apache.xerces.jaxp.DocumentBuilderFactoryImpl.class.getName(),this.getClass().getClassLoader());
            if(DISABLE_DTDs) {
                documentBuilderFactory.setFeature(getFeatures_disallow_doctype_decl(), true);
            }
            return documentBuilderFactory;
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }
    @Override
    protected DatatypeFactory newDatatypeFactory() throws XMLException{
        try{
            // force xerces impl
            /**System.setProperty("javax.xml.datatype.DatatypeFactory", org.apache.xerces.jaxp.datatype.DatatypeFactoryImpl.class.getName());
            return DatatypeFactory.newInstance();*/
            return DatatypeFactory.newInstance(org.apache.xerces.jaxp.datatype.DatatypeFactoryImpl.class.getName(), this.getClass().getClassLoader());
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }
    @Override
    protected javax.xml.parsers.SAXParserFactory newSAXParserFactory() throws XMLException{
        try{
            // force xerces impl
            /**System.setProperty("javax.xml.parsers.SAXParserFactory", org.apache.xerces.jaxp.SAXParserFactoryImpl.class.getName());
            return javax.xml.parsers.SAXParserFactory.newInstance();*/
            javax.xml.parsers.SAXParserFactory saxParserFactory = javax.xml.parsers.SAXParserFactory.newInstance(org.apache.xerces.jaxp.SAXParserFactoryImpl.class.getName(), this.getClass().getClassLoader());
            if(DISABLE_DTDs) {
                saxParserFactory.setFeature(getFeatures_disallow_doctype_decl(), true);
            }
            return saxParserFactory;
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }
    /**
    @Override
    protected javax.xml.stream.XMLEventFactory newXMLEventFactory() throws XMLException{
        try{            
            // force xerces impl
//          System.setProperty("javax.xml.stream.XMLEventFactory", org.apache.xerces.stax.XMLEventFactoryImpl.class.getName());
//          return javax.xml.stream.XMLEventFactory.newFactory();
            return javax.xml.stream.XMLEventFactory.newFactory(org.apache.xerces.stax.XMLEventFactoryImpl.class.getName(), this.getClass().getClassLoader());
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }
    */
    @Override
    protected SchemaFactory newSchemaFactory() throws XMLException{
        try{
            // force xerces impl
            SchemaFactory schemaFactory = SchemaFactory.newInstance(XMLConstants.W3C_XML_SCHEMA_NS_URI,
                    org.apache.xerces.jaxp.validation.XMLSchemaFactory.class.getName(), this.getClass().getClassLoader());
            if(DISABLE_DTDs) {
                schemaFactory.setFeature(getFeatures_disallow_doctype_decl(), true);
            }
            return schemaFactory;
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }
    
    // XALAN
    @Override
    protected TransformerFactory newTransformerFactory() throws XMLException{
        try{
            // force xalan impl
            /**System.setProperty("javax.xml.transform.TransformerFactory", org.apache.xalan.processor.TransformerFactoryImpl.class.getName());
            return TransformerFactory.newInstance();*/
            TransformerFactory transformerFactory = TransformerFactory.newInstance(org.apache.xalan.processor.TransformerFactoryImpl.class.getName(), this.getClass().getClassLoader());
            /**if(DISABLE_DTDs) {
                transformerFactory.setAttribute(javax.xml.XMLConstants.ACCESS_EXTERNAL_DTD, "");
                transformerFactory.setAttribute(javax.xml.XMLConstants.ACCESS_EXTERNAL_STYLESHEET, "");
            }*/
            return transformerFactory;
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }
    @Override
    protected XPathFactory newXPathFactory() throws XMLException{
        try{
            /**return XPathFactory.newInstance();*/
            // force xalan impl
            return XPathFactory.newInstance(XPathFactory.DEFAULT_OBJECT_MODEL_URI,
                    org.apache.xpath.jaxp.XPathFactoryImpl.class.getName(), this.getClass().getClassLoader());
        }catch(Exception e){
            throw new XMLException(e.getMessage(),e);
        }
    }

}