Roundtrip.java

//package org.xmlpull.v1.samples;

import java.io.*;

import org.kxml2.io.*;
import org.xmlpull.v1.*;
public class Roundtrip {
	//private static final String FEATURE_XML_ROUNDTRIP=
	//    "http://xmlpull.org/v1/doc/features.html#xml-roundtrip";

	XmlPullParser parser;
	XmlSerializer serializer;

	public Roundtrip(XmlPullParser parser, XmlSerializer serializer) {
		this.parser = parser;
		this.serializer = serializer;
	}

	public void writeStartTag() throws XmlPullParserException, IOException {
		//check forcase when feature xml roundtrip is supported
		//if (parser.getFeature (FEATURE_XML_ROUNDTRIP)) {
		//TODO: how to do pass through string with actual start tag in getText()
		//return;
		//}
		if (!parser.getFeature(parser.FEATURE_REPORT_NAMESPACE_ATTRIBUTES)) {
			for (int i = parser.getNamespaceCount(parser.getDepth() - 1);
				i < parser.getNamespaceCount(parser.getDepth()) - 1;
				i++) {
				serializer.setPrefix(
					parser.getNamespacePrefix(i),
					parser.getNamespaceUri(i));
			}
		}
		serializer.startTag(parser.getNamespace(), parser.getName());

		for (int i = 0; i < parser.getAttributeCount(); i++) {
			serializer.attribute(
				parser.getAttributeNamespace(i),
				parser.getAttributeName(i),
				parser.getAttributeValue(i));
		}
		//serializer.closeStartTag();
	}

	public void writeToken() throws XmlPullParserException, IOException {
		switch (parser.getEventType()) {
			case XmlPullParser.START_DOCUMENT :
				//serializer.startDocument (null,
				break;

			case XmlPullParser.END_DOCUMENT :
				serializer.endDocument();
				break;

			case XmlPullParser.START_TAG :
				writeStartTag();
				break;

			case XmlPullParser.END_TAG :
				serializer.endTag(parser.getNamespace(), parser.getName());
				break;

			case XmlPullParser.IGNORABLE_WHITESPACE :
				//comment it to remove ignorable whtespaces from XML infoset
				serializer.ignorableWhitespace(parser.getText());
				break;

			case XmlPullParser.TEXT :
				serializer.text(parser.getText());
				break;

			case XmlPullParser.ENTITY_REF :
				serializer.entityRef(parser.getName());
				break;

			case XmlPullParser.CDSECT :
				serializer.cdsect(parser.getText());
				break;

			case XmlPullParser.PROCESSING_INSTRUCTION :
				serializer.processingInstruction(parser.getText());
				break;

			case XmlPullParser.COMMENT :
				serializer.comment(parser.getText());
				break;

			case XmlPullParser.DOCDECL :
				serializer.docdecl(parser.getText());
				break;

			default :
				throw new RuntimeException(
					"unrecognized event: " + parser.getEventType());
		}
	}

	public void roundTrip() throws XmlPullParserException, IOException {
		while (parser.getEventType() != parser.END_DOCUMENT) {
			writeToken();
			parser.nextToken();
		}
		writeToken();
	}

	public static void main(String[] args) throws Exception {
		if (args.length == 0)
			throw new RuntimeException("input xml file name expected");
		for (int i = 0; i < args.length; i++) {
			System.out.println("processing: " + args[i]);
			XmlPullParser pp = new KXmlParser();
			pp.setFeature (XmlPullParser.FEATURE_PROCESS_NAMESPACES, true);
			XmlSerializer serializer = new KXmlSerializer();

			pp.setInput(new FileReader(args[i]));
			serializer.setOutput(System.out, null);

			(new Roundtrip(pp, serializer)).roundTrip();
			serializer.flush();
		}
	}

}