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XMLStreamWriter write tag containing colon

When I use colon in the tag name like in the example below, it ends up in error (there is no problem with tags without the colon).
package test;
import java.io.StringReader;
import java.io.StringWriter;
import javax.xml.stream.XMLOutputFactory;
import javax.xml.stream.XMLStreamException;
import javax.xml.stream.XMLStreamWriter;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerConfigurationException;
import javax.xml.transform.TransformerException;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
public class SomeClass{
public StringWriter test() throws XMLStreamException, TransformerConfigurationException, TransformerException {
StringWriter stringOut = new StringWriter();
XMLStreamWriter xmlWriter = XMLOutputFactory.newInstance().createXMLStreamWriter(stringOut);
xmlWriter.writeStartDocument("UTF-8", "1.0");
xmlWriter.writeStartElement("SomeWordHere");
{
xmlWriter.writeStartElement("SomeName:enable");//<--- notice the colon
xmlWriter.writeCharacters("true");
xmlWriter.writeEndElement();
}
xmlWriter.writeEndElement();
xmlWriter.writeEndDocument();
xmlWriter.flush();
xmlWriter.close();
Transformer transformer = TransformerFactory.newInstance().newTransformer();
transformer.setOutputProperty(OutputKeys.STANDALONE, "no");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
transformer.setOutputProperty(OutputKeys.METHOD, "xml");
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
StringWriter formattedStringWriter = new StringWriter();
transformer.transform(new StreamSource(new StringReader(stringOut.toString())), new StreamResult(formattedStringWriter));
return formattedStringWriter;
}
}
How to write the tag that would still conain the colon and would not end up in error?
I am trying to emulate the XML output (Collada DAE) produced by LEGO Stud.io software, there are sections like the one below containing tag names with colons.
<library_materials>
<material id="material_id_7" name="SOLID-BLUE">
<instance_effect url="#effect_id_7-fx" />
<extra>
<technique profile="eyesight">
<ScratchBump:enable> true </ScratchBump:enable>
<MinScratchStrength:value> 0 </MinScratchStrength:value>
<MaxScratchStrength:value> 0.2 </MaxScratchStrength:value>
<BigScratch:enable> true </BigScratch:enable>
<SmallScratch:enable> true </SmallScratch:enable>
</technique>
</extra>
</material>
</library_materials>

Colon is used for namespaces and per "Namespaces in XML" specification, it cannot be used in entity names.
The specification states:
[Definition: A document is namespace-well-formed if it conforms to
this specification. ]
It follows that in a namespace-well-formed document:
All element and attribute names contain either zero or one colon;
No entity names, processing instruction targets, or notation names contain any colons.
You can use a trick that is to declare "SomeName" as a namespace as it is suggested in this question: xml schema validation error "prefix is not bound".
On the other hand, "Extensible Markup Language" Specification state that:
Note:
The Namespaces in XML Recommendation [XML Names] assigns a meaning to
names containing colon characters. Therefore, authors should not use
the colon in XML names except for namespace purposes, but XML
processors must accept the colon as a name character.
If you change the parser you can get what you want:
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
public class CreateXmlFileDemo {
public static void main(String[] args) {
try {
DocumentBuilderFactory dbFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder dBuilder = dbFactory.newDocumentBuilder();
Document doc = dBuilder.newDocument();
Element rootElement = doc.createElement("SomeName:enable");
doc.appendChild(rootElement);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
DOMSource source = new DOMSource(doc);
StreamResult consoleResult = new StreamResult(System.out);
transformer.transform(source, consoleResult);
} catch (Exception e) {
e.printStackTrace();
}
}
}
Reference: https://www.w3.org/TR/REC-xml-names/

XML Transformation using DOMSource, DOMResult & XSLT

I am trying to transform the following XML
<PHONEBOOK>
<PERSON>
<NAME>Ren1</NAME>
<EMAIL>ren1#gmail.com</EMAIL>
<TELEPHONE>999-999-9999</TELEPHONE>
<WEB>www.ren1.com</WEB>
</PERSON>
<PERSON>
<NAME>Ren2</NAME>
<EMAIL>ren2#gmail.com</EMAIL>
<TELEPHONE>999-999-9999</TELEPHONE>
<WEB>www.ren2.com</WEB>
</PERSON>
<PERSON>
<NAME>Ren3</NAME>
<EMAIL>ren3#gmail.com</EMAIL>
<TELEPHONE>999-999-9999</TELEPHONE>
<WEB>www.ren3.com</WEB>
</PERSON>
</PHONEBOOK>
to
<Names><Name>Ren1</Name><Name>Ren2</Name><Name>Ren3</Name></Names>
using DOMSource, DOMResult and XSLT.
XSLT used is as follows
<?xml version="1.0"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
version="1.0">
<xsl:output omit-xml-declaration="yes" method="xml"></xsl:output>
<xsl:template match="/">
<Names>
<xsl:for-each select="PHONEBOOK/PERSON">
<Name>
<xsl:value-of select="NAME" />
</Name>
</xsl:for-each>
</Names>
Java Code used for transformation:
package test1;
import java.io.IOException;
import java.io.StringWriter;
import java.io.ObjectInputStream.GetField;
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.DOMResult;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.w3c.dom.Document;
import org.w3c.dom.Node;
import org.xml.sax.SAXException;
public class Test2 {
public static void main(String[] args) throws TransformerException,
ParserConfigurationException, SAXException, IOException {
// TODO Auto-generated method stub
//Stylesheet
StreamSource stylesource = new StreamSource(
"src/test1/transform_stylesheet1.xsl");
DocumentBuilderFactory docbFactory = DocumentBuilderFactory
.newInstance();
DocumentBuilder dBuilder = docbFactory.newDocumentBuilder();
//source XML
Document sourceDoc = dBuilder.parse("src/test1/Sample1.xml");
DOMSource source = new DOMSource(sourceDoc);
TransformerFactory transformerFactory = TransformerFactory
.newInstance();
Transformer transformer = transformerFactory
.newTransformer(stylesource);
Document document = dBuilder.newDocument();
DOMResult result = new DOMResult(document);
transformer.transform(source, result);
Node resultDoc = ((Document) result.getNode()).getDocumentElement();
System.out.println(resultDoc.getChildNodes().getLength());
// print the result
StringWriter writer = new StringWriter();
transformer.transform(new DOMSource(resultDoc), new StreamResult(writer));
String str = writer.toString();
System.out.println(str);
}
}
Output of the above is as follows:
3 <Names/>
but i expect,
3
<Names><Name>Ren1</Name><Name>Ren2</Name><Name>Ren3</Name></Names>
i debugged the code and found that 'resultDoc' has the content which i expect. Am i missing something while printing the result?

Your problem is that you're using the same transformer for the stylesheet processing and the output. That means, the stylesheet is applied again, but this time to the <Names><Name>Ren1</Name>...</Names> xml. You can imagine that this doesn't give the results you want.
Change your code to:
// print the result
StringWriter writer = new StringWriter();
Transformer transformer2 = transformerFactory.newTransformer();
transformer2.transform(new DOMSource(resultDoc), new StreamResult(writer));
String str = writer.toString();
System.out.println(str);
and it should work.
As #Abel mentions, you can also do the stylesheet processing and the to String in one go:
StringWriter writer = new StringWriter();
transformer.transform(source, new StreamResult(writer));
String str = writer.toString();
System.out.println(str);
You don't need the DOMResult and DOMSource variables then.

update the input XML file with namespace in JAVA using DOM parser

How to update the XML node from <ns0:Request> to <ns1:Request xmlns:ns1="with some URL">
in Java using DOM parser.
I do not want to use the replaceAll() method.

You can do the following using the Node.replaceChild(Node, Node) method:
http://docs.oracle.com/javase/7/docs/api/org/w3c/dom/Node.html#replaceChild%28org.w3c.dom.Node,%20org.w3c.dom.Node%29
import javax.xml.parsers.*;
import javax.xml.transform.*;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
public class Demo {
public static void main(String[] args) throws Exception {
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
dbf.setNamespaceAware(true);
DocumentBuilder db = dbf.newDocumentBuilder();
// Create original document
Document document = db.newDocument();
Element root = document.createElementNS("urn:FOO", "ns0:Root");
document.appendChild(root);
Element request = document.createElementNS("urn:FOO", "ns0:Request");
root.appendChild(request);
// Create new Request element.
Element newRequest = document.createElementNS("urn:BAR", "ns1:Request");
// Replace Request element
root.replaceChild(newRequest, request);
// Output the new document
TransformerFactory tf = TransformerFactory.newInstance();
Transformer t = tf.newTransformer();
DOMSource source = new DOMSource(document);
StreamResult result = new StreamResult(System.out);
t.transform(source, result);
}
}

Serialize DOM to FileOutputStream using Xerces

I am using this link to generate XML file using DOM. It says that "Xerces parser is bundled with the JDK 1.5 distribution.So you need not download the parser separately."
However, when I write the following line in my Eclipse Helios it gives compile-time error even though I have Java 1.6 in my system.
import org.apache.xml.serialize.XMLSerializer;
Why is it so?

Xerces is indeed bundled with the JDK but you should use it with the JAXP API under javax.xml.parsers. Check the output of the program below.
Also, to serialize an XML Document, you should use DOM Level 3 Load and Save (present in the JDK) or an XSLT transformation with no stylesheet (identity transformation). The rest is dependent on a specific implementation. The Xerces XMLSerializer is deprecated:
Deprecated. This class was deprecated in Xerces 2.9.0. It is recommended that new applications use the DOM Level 3 LSSerializer or JAXP's Transformation API for XML (TrAX) for serializing XML. See the Xerces documentation for more information.
Here is an example of serialization with DOM level 3:
import org.w3c.dom.*;
import org.w3c.dom.bootstrap.DOMImplementationRegistry;
import org.w3c.dom.ls.*;
public class DOMExample3 {
public static void main(String[] args) throws Exception {
DOMImplementationRegistry registry = DOMImplementationRegistry.newInstance();
DOMImplementationLS impl = (DOMImplementationLS) registry.getDOMImplementation("XML 3.0 LS 3.0");
if (impl == null) {
System.out.println("No DOMImplementation found !");
System.exit(0);
}
System.out.printf("DOMImplementationLS: %s\n", impl.getClass().getName());
LSParser parser = impl.createLSParser(
DOMImplementationLS.MODE_SYNCHRONOUS,
"http://www.w3.org/TR/REC-xml");
// http://www.w3.org/2001/XMLSchema
System.out.printf("LSParser: %s\n", parser.getClass().getName());
if (args.length == 0) {
System.exit(0);
}
Document doc = parser.parseURI(args[0]);
LSSerializer serializer = impl.createLSSerializer();
LSOutput output = impl.createLSOutput();
output.setEncoding("UTF-8");
output.setByteStream(System.out);
serializer.write(doc, output);
System.out.println();
}
}
Here is an example with an identity transformation:
import org.w3c.dom.Document;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Result;
import javax.xml.transform.Source;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
public class DOMExample2 {
public static void main(String[] args) throws Exception {
DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();
DocumentBuilder parser = factory.newDocumentBuilder();
System.out.println("Parsing XML document...");
Document doc;
doc = parser.parse(args[0]);
// Xerces Java 2
/* Deprecated. This class was deprecated in Xerces 2.9.0.
* It is recommended that new applications use the DOM Level 3
* LSSerializer or JAXP's Transformation API for XML (TrAX)
* for serializing XML and HTML.
* See the Xerces documentation for more information.
*/
/*
System.out.println("XERCES: Displaying XML document...");
OutputFormat of = new OutputFormat(doc, "ISO-8859-1", true);
PrintWriter pw = new PrintWriter(System.out);
BaseMarkupSerializer bms = new XMLSerializer(pw, of);
bms.serialize(doc);
*/
// JAXP
System.out.println("JAXP: Displaying XML document...");
TransformerFactory transFactory = TransformerFactory.newInstance();
System.out.println(transFactory.getClass().getName());
//transFactory.setAttribute("indent-number", 2);
Transformer idTransform = transFactory.newTransformer();
idTransform.setOutputProperty(OutputKeys.METHOD, "xml");
idTransform.setOutputProperty(OutputKeys.INDENT,"yes");
// Apache default indentation is 0
idTransform.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
Source input = new DOMSource(doc);
Result output = new StreamResult(System.out);
idTransform.transform(input, output);
}
}

It will be in, IIRC, com.sun.org.apache.xml.serialize.XMLSerializer. However, those are private classes and likely to change at any time. I suggest using the standard public APIs (javax.* and friends) instead. (Use the transform API without any XSLT.)

Standardise on a XML reader methodology

In an open source project I maintain, we have at least three different ways of reading, processing and writing XML files and I would like to standardise on a single method for ease of maintenance and stability.
Currently all of the project files use XML from the configuration to the stored data, we're hoping to migrate to a simple database at some point in the future but will still need to read/write some form of XML files.
The data is stored in an XML format that we then use a XSLT engine (Saxon) to transform into the final HTML files.
We currently utilise these methods:
- XMLEventReader/XMLOutputFactory (javax.xml.stream)
- DocumentBuilderFactory (javax.xml.parsers)
- JAXBContext (javax.xml.bind)
Are there any obvious pros and cons to each of these?
Personally, I like the simplicity of DOM (Document Builder), but I'm willing to convert to one of the others if it makes sense in terms of performance or other factors.
Edited to add:
There can be a significant number of files read/written when the project runs, between 100 & 10,000 individual files of around 5Kb each

It depends on what you are doing with the data.
If you are simply performing XSLT transforms on XML files to produce HTML files then you may not need to touch a parser directly:
import java.io.File;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
public class Demo {
public static void main(String[] args) throws Exception {
TransformerFactory tf = TransformerFactory.newInstance();
StreamSource xsltTransform = new StreamSource(new File("xslt.xml"));
Transformer transformer = tf.newTransformer(xsltTransform);
StreamSource source = new StreamSource(new File("source.xml"));
StreamResult result = new StreamResult(new File("result.html"));
transformer.transform(source, result);
}
}
If you need to make changes to the input document before you transform it, DOM is a convenient mechanism for doing this:
import java.io.File;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
import org.w3c.dom.Document;
public class Demo {
public static void main(String[] args) throws Exception {
TransformerFactory tf = TransformerFactory.newInstance();
StreamSource xsltTransform = new StreamSource(new File("xslt.xml"));
Transformer transformer = tf.newTransformer(xsltTransform);
DocumentBuilderFactory dbf = DocumentBuilderFactory.newInstance();
DocumentBuilder db = dbf.newDocumentBuilder();
Document document = db.parse(new File("source.xml"));
// modify the document
DOMSource source = new DOMSource(document);
StreamResult result = new StreamResult(new File("result.html"));
transformer.transform(source, result);
}
}
If you prefer a typed model to make changes to the data then JAXB is a perfect fit:
import java.io.File;
import javax.xml.bind.JAXBContext;
import javax.xml.bind.Unmarshaller;
import javax.xml.bind.util.JAXBSource;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.stream.StreamResult;
import javax.xml.transform.stream.StreamSource;
public class Demo {
public static void main(String[] args) throws Exception {
TransformerFactory tf = TransformerFactory.newInstance();
StreamSource xsltTransform = new StreamSource(new File("xslt.xml"));
Transformer transformer = tf.newTransformer(xsltTransform);
JAXBContext jc = JAXBContext.newInstance("com.example.model");
Unmarshaller unmarshaller = jc.createUnmarshaller();
Model model = (Model) unmarshaller.unmarshal(new File("source.xml"));
// modify the domain model
JAXBSource source = new JAXBSource(jc, model);
StreamResult result = new StreamResult(new File("result.html"));
transformer.transform(source, result);
}
}

This is a very subjective topic. It primarily depends on how you are going to use the xml and size of XML. If XML is (always) small enough to be loaded in to memory, then you don't have to worry about memory foot print. You can use DOM parser. If you need to a parse through 150 MB xml you may want to think of using SAX. etc.