Is it possible using StAX (specifically woodstox) to format the output xml with newlines and tabs, i.e. in the form:
<element1> <element2> someData </element2> </element1>
instead of:
<element1><element2>someData</element2></element1>
If this is not possible in woodstox, is there any other lightweight libs that can do this?
There is com.sun.xml.txw2.output.IndentingXMLStreamWriter
XMLOutputFactory xmlof = XMLOutputFactory.newInstance();
XMLStreamWriter writer = new IndentingXMLStreamWriter(xmlof.createXMLStreamWriter(out));
Via the JDK: transformer.setOutputProperty(OutputKeys.INDENT, "yes");.
If you're using the StAX cursor API, you can indent the output by wrapping the XMLStreamWriter in an indenting proxy. I tried this in my own project and it worked nicely.
Using the JDK Transformer:
public String transform(String xml) throws XMLStreamException, TransformerException
{
Transformer t = TransformerFactory.newInstance().newTransformer();
t.setOutputProperty(OutputKeys.INDENT, "yes");
t.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2");
Writer out = new StringWriter();
t.transform(new StreamSource(new StringReader(xml)), new StreamResult(out));
return out.toString();
}
Rather than relying on a com.sun...class that might go away (or get renamed com.oracle...class), I recommend downloading the StAX utility classes from java.net. This package contains a IndentingXMLStreamWriter class that works nicely. (Source and javadoc are included in the download.)
How about StaxMate:
http://www.cowtowncoder.com/blog/archives/2006/09/entry_21.html
Works well with Woodstox, fast, low-memory usage (no in-memory tree built), and indents like so:
SMOutputFactory sf = new SMOutputFactory(XMLOutputFactory.newInstance());
SMOutputDocument doc = sf.createOutputDocument(new FileOutputStream("output.xml"));
doc.setIndentation("\n ", 1, 2); // for unix linefeed, 2 spaces per level
// write doc like:
SMOutputElement root = doc.addElement("element1");
root.addElement("element2").addCharacters("someData");
doc.closeRoot(); // important, flushes, closes output
if you are using XMLEventWriter, then an easier way to do that is:
XMLOutputFactory outputFactory = XMLOutputFactory.newInstance();
XMLEventWriter writer = outputFactory.createXMLEventWriter(w);
XMLEventFactory eventFactory = XMLEventFactory.newInstance();
Characters newLine = eventFactory.createCharacters("\n");
writer.add(startRoot);
writer.add(newLine);
Not sure about stax, but there was a recent discussion about pretty printing xml here
this was my attempt at a solution
How to pretty print XML from Java?
using the org.dom4j.io.OutputFormat.createPrettyPrint() method
If you're using the iterating method (XMLEventReader), can't you just attach a new line '\n' character to the relevant XMLEvents when writing to your XML file?
With Spring Batch this requires a subclass since this JIRA BATCH-1867
public class IndentingStaxEventItemWriter<T> extends StaxEventItemWriter<T> {
@Setter
@Getter
private boolean indenting = true;
@Override
protected XMLEventWriter createXmlEventWriter( XMLOutputFactory outputFactory, Writer writer) throws XMLStreamException {
if ( isIndenting() ) {
return new IndentingXMLEventWriter( super.createXmlEventWriter( outputFactory, writer ) );
}
else {
return super.createXmlEventWriter( outputFactory, writer );
}
}
}
But this requires an additionnal dependency because Spring Batch does not include the code to indent the StAX output:
<dependency>
<groupId>net.java.dev.stax-utils</groupId>
<artifactId>stax-utils</artifactId>
<version>20070216</version>
</dependency>
