site.util.EvXmlUtil.java Source code

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Here is the source code for site.util.EvXmlUtil.java

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/***
 * Copyright (C) 2010 Johan Henriksson
 * This code is under the Endrov / BSD license. See www.endrov.net
 * for the full text and how to cite.
 */
package site.util;

import java.io.*;
import java.util.List;

import org.jdom2.Attribute;
import org.jdom2.Document;
import org.jdom2.Element;
import org.jdom2.JDOMException;
import org.jdom2.input.SAXBuilder;
import org.jdom2.output.Format;
import org.jdom2.output.XMLOutputter;
import org.xml.sax.EntityResolver;
import org.xml.sax.InputSource;

/**
 * Utility functions for XML
 * @author Johan Henriksson
 */
public class EvXmlUtil {

    public static Document readXML(File filename) throws IOException, JDOMException {
        //      FileInputStream fileInputStream = new FileInputStream(filename);
        SAXBuilder saxBuilder = new SAXBuilder();
        Document document = saxBuilder.build(filename);
        return document;
    }

    public static class NoOpEntityResolver implements EntityResolver {
        @SuppressWarnings("deprecation")
        public InputSource resolveEntity(String publicId, String systemId) {
            return new InputSource(new StringBufferInputStream(""));
        }
    }

    public static Document readXML(Reader c) throws Exception {
        @SuppressWarnings("deprecation")
        SAXBuilder saxBuilder = new SAXBuilder(false); //No validation
        //saxBuilder.setFeature("http://apache.org/xml/features/nonvalidating/load-external-dtd", false); //xerxes only
        saxBuilder.setEntityResolver(new NoOpEntityResolver()); //http://www.jdom.org/docs/faq.html#a0350
        Document document = saxBuilder.build(c);
        return document;
    }

    public static List<Element> getChildrenE(Element root, String name) {
        return root.getChildren(name);
    }

    public static List<Element> getChildrenE(Element root) {
        return root.getChildren();
    }

    public static String prettyPrint(Element e) {
        try {
            //TODO not sure if this works
            Document doc = new Document((Element) e.clone()); //need to clone?
            return xmlToString(doc);
        } catch (Exception e1) {
            e1.printStackTrace();
            return null;
        }
        /*      
                  
                  
              StringBuffer b=new StringBuffer();
              prettyPrint(e, b);
              return b.toString();*/
    }

    public static void prettyPrint(Element e, StringBuffer b) {
        b.append("<" + e.getName() + ">");
        for (Object o : e.getChildren())
            prettyPrint((Element) o, b);
        b.append("</" + e.getName() + ">");
    }

    /**
     * Checks if name and attributes equal, not content
     */
    public static boolean elementsEqual(Element a, Element b) {
        if (a.getName().equals(b.getName())) {
            for (Object o : a.getAttributes()) {
                Attribute attra = (Attribute) o;
                Attribute attrb = b.getAttribute(attra.getName());
                if (attrb == null)
                    return false;
                if (!attra.getValue().equals(attrb.getValue()))
                    return false;
            }
            for (Object o : b.getAttributes()) {
                Attribute attrb = (Attribute) o;
                Attribute attra = a.getAttribute(attrb.getName());
                if (attra == null)
                    return false;
                if (!attrb.getValue().equals(attra.getValue()))
                    return false;
            }
            return true;
        } else
            return false;
    }

    /**
     * Merge two XML-documents
     * @param to
     * @param from
     */
    public static void mergeXML(Element to, Element from) {
        //For every element to be added
        for (Object o : from.getChildren()) {
            Element frome = (Element) o;

            //Find matching element in destination
            Element match = null;
            for (Object o2 : to.getChildren()) {
                Element toe = (Element) o2;
                if (elementsEqual(frome, toe)) {
                    match = toe;
                    break;
                }
            }

            //Add content
            if (match == null)
                to.addContent((Element) frome.clone());
            else
                mergeXML(match, frome);
        }
    }

    /**
     * Write XML-document to disk
     */
    public static void writeXmlData(Document doc, File file) throws Exception {
        //FileWriter writer = new FileWriter(file);
        FileOutputStream writer2 = new FileOutputStream(file);
        writeXmlData(doc, writer2);
        writer2.close();
    }

    /**
     * Write XML-document to stream
     */
    public static void writeXmlData(Document doc, OutputStream os) throws Exception {
        Format format = Format.getPrettyFormat();
        XMLOutputter outputter = new XMLOutputter(format);
        outputter.output(doc, os);
    }

    /**
     * Write XML-document to disk
     */
    public static String xmlToString(Document doc) throws Exception {
        Format format = Format.getPrettyFormat();
        XMLOutputter outputter = new XMLOutputter(format);
        StringWriter writer = new StringWriter();
        outputter.output(doc, writer);
        return writer.toString();
    }

    public static Element stringToXml(String s) throws Exception {
        SAXBuilder saxBuilder = new SAXBuilder();
        Document document = saxBuilder.build(new StringReader(s));
        Element element = document.getRootElement();
        return element;
    }

}