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copied!<p>Parsing XML documents using DOM doesn't scale.</p> <p>This <a href="http://groovy.codehaus.org/" rel="nofollow noreferrer">Groovy</a>-script is using StAX (Streaming API for XML) to split an XML document between the top-level elements (that shares the same QName as the first child of the root-document). It's pretty fast, handles arbitrary large documents and is very useful when you want to split a large batch-file into smaller pieces.</p> <p>Requires Groovy on Java 6 or a StAX API and implementation such as <a href="http://woodstox.codehaus.org/" rel="nofollow noreferrer">Woodstox</a> in the CLASSPATH</p> <pre><code>import javax.xml.stream.* pieces = 5 input = "input.xml" output = "output_%04d.xml" eventFactory = XMLEventFactory.newInstance() fileNumber = elementCount = 0 def createEventReader() { reader = XMLInputFactory.newInstance().createXMLEventReader(new FileInputStream(input)) start = reader.next() root = reader.nextTag() firstChild = reader.nextTag() return reader } def createNextEventWriter () { println "Writing to '${filename = String.format(output, ++fileNumber)}'" writer = XMLOutputFactory.newInstance().createXMLEventWriter(new FileOutputStream(filename), start.characterEncodingScheme) writer.add(start) writer.add(root) return writer } elements = createEventReader().findAll { it.startElement && it.name == firstChild.name }.size() println "Splitting ${elements} <${firstChild.name.localPart}> elements into ${pieces} pieces" chunkSize = elements / pieces writer = createNextEventWriter() writer.add(firstChild) createEventReader().each { if (it.startElement && it.name == firstChild.name) { if (++elementCount > chunkSize) { writer.add(eventFactory.createEndDocument()) writer.flush() writer = createNextEventWriter() elementCount = 0 } } writer.add(it) } writer.flush() </code></pre>

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