source: tmcsimulator-scriptbuilder/trunk/src/scriptbuilder/structures/XMLBuilder.java @ 206

package scriptbuilder.structures;



import java.io.IOException;

import java.io.StringReader;

import java.io.StringWriter;

import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;

import javax.xml.transform.OutputKeys;

import javax.xml.transform.Transformer;

import javax.xml.transform.TransformerException;

import javax.xml.transform.TransformerFactory;

import javax.xml.transform.dom.DOMSource;

import javax.xml.transform.stream.StreamResult;

import org.w3c.dom.Document;

import org.xml.sax.InputSource;

import org.xml.sax.SAXException;



/**

 * Utility methods that build XML elements from content strings.

 * @author Bryan McGuffin

 */

public class XMLBuilder

{



    /**

     * XML-style opening tag. Example: if given string "my_tag", returns

     * "<my_tag>".

     *

     * @param s the XML element to be included in the tag.

     * @return the properly formatted tag

     */

    public static String openTag(String s)

    {

        return "<" + s + ">";

    }



    /**

     * XML-style closing tag. Example: if given string "my_tag", returns

     * "</my_tag>".

     *

     * @param s the XML element to be included in the tag.

     * @return the properly formatted tag

     */

    public static String closeTag(String s)

    {

        return "</" + s + ">\n";

    }



    /**

     * XML-style empty tag. Example: if given string "my_tag", returns

     * "<my_tag/>".

     *

     * @param s the XML element to be included in the tag.

     * @return the properly formatted tag

     */

    public static String emptyTag(String s)

    {

        return "<" + s + "/>\n";

    }



    /**

     * Creates a pair of XML open and close tags to wrap a simple line of data.

     * Useful if only one element need be enclosed in this particular tag.

     *

     * @param s the data to be wrapped

     * @param e the XML element represented by the data

     * @return an XML string of the format <my_tag>some_data_goes_here</my_tag>

     */

    public static String simpleTag(String s, ELEMENT e)

    {

        String output = "";

        if (s == null)

        {

            s = "";

        }



        output += openTag(e.tag);

        output += s;

        output += closeTag(e.tag);



        return output;

    }



    /**

     * @return the xml string with the link to external DTD for XML script files.

     */

    public static String externalDTD()

    {

        return "<!DOCTYPE TMC_SCRIPT SYSTEM \"incident_script.dtd\">\n";

    }

    /**

     * @return The xml string that starts the document.

     */

    public static String xmlHeader()

    {

        return "<?xml version=\"1.0\" encoding=\"ISO-8859-1\"?>\n";

    }

    /**

     * Prettyprint an XML string.

     * @param xmlString (works best if it contains no newlines)

     * @return String that has been nicely formatted with indentation

     */

    public static String prettyPrintXML(String xmlString)

    {

        Document xmlDoc = null;

        String formattedXML = "";

        try {

            xmlDoc = toXmlDocument(xmlString);

            formattedXML = prettyprintdoc(xmlDoc);

        } catch (ParserConfigurationException | SAXException | IOException

                | TransformerException e) {

            e.printStackTrace();

        }

        // Prepend the header and externalDTD lines.  (This must be done after

        // prettyprinting, which tries to read the externalDTD if the link is present.)

        // Fixes #239.

        formattedXML = xmlHeader() + externalDTD() + formattedXML;

        return formattedXML;

    }

    

 

    /**

     * Prettyprint an XML document.

     * @param document an "ugly" XML document

     * @return String nicely formatted XML with indentation

     * @throws TransformerException 

     */

    public static String prettyprintdoc(Document document)

            throws TransformerException {

        TransformerFactory transformerFactory = TransformerFactory

                .newInstance();

        Transformer transformer = transformerFactory.newTransformer();

        transformer.setOutputProperty(OutputKeys.INDENT, "yes");

        transformer.setOutputProperty(

                "{http://xml.apache.org/xslt}indent-amount", "2");

        transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, "yes");

        DOMSource source = new DOMSource(document);

        StringWriter strWriter = new StringWriter();

        StreamResult result = new StreamResult(strWriter);

 

        transformer.transform(source, result);

 

        return strWriter.getBuffer().toString();

 

    }

 

    /** Create an XML Document from a string that is in xml format.

     * 

     * @param str xml format content

     * @return Document containing the specified content.

     * @throws ParserConfigurationException

     * @throws SAXException

     * @throws IOException 

     */

    public static Document toXmlDocument(String str)

            throws ParserConfigurationException, SAXException, IOException {

 

        DocumentBuilderFactory docBuilderFactory = DocumentBuilderFactory

                .newInstance();

        DocumentBuilder docBuilder = docBuilderFactory.newDocumentBuilder();

        Document document = docBuilder.parse(new InputSource(new StringReader(

                str)));

 

        return document;

    }

}