DomUtil.java

/**
 * Copyright (c) 2020, RTE (http://www.rte-france.com)
 * This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/.
 */
package com.powsybl.diagram.util;

import com.powsybl.commons.exceptions.UncheckedParserConfigurationException;
import com.powsybl.commons.exceptions.UncheckedTransformerException;
import org.w3c.dom.Document;

import javax.xml.XMLConstants;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import java.io.Writer;

/**
 * @author Geoffroy Jamgotchian {@literal <geoffroy.jamgotchian at rte-france.com>}
 */
public final class DomUtil {

    private DomUtil() {
    }

    public static DocumentBuilder getDocumentBuilder() {
        try {
            DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
            dbf.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
            dbf.setAttribute(XMLConstants.ACCESS_EXTERNAL_SCHEMA, "");
            return dbf.newDocumentBuilder();
        } catch (ParserConfigurationException e) {
            throw new UncheckedParserConfigurationException(e);
        }
    }

    public static void transformDocument(Document document, Writer writer) {
        try {
            DOMSource source = new DOMSource(document);
            StreamResult result = new StreamResult(writer);
            Transformer transformer = createTransformer();
            transformer.setOutputProperty(OutputKeys.INDENT, "yes");
            transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
            transformer.transform(source, result);
        } catch (TransformerException e) {
            throw new UncheckedTransformerException(e);
        }
    }

    public static Transformer createTransformer() throws TransformerConfigurationException {
        TransformerFactory transformerFactory = TransformerFactory.newInstance();
        transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_DTD, "");
        transformerFactory.setAttribute(XMLConstants.ACCESS_EXTERNAL_STYLESHEET, "");
        return transformerFactory.newTransformer();
    }
}