Re: [Xml-coreutils-discuss] Where to start?
Status: Alpha
Brought to you by:
lbreyer
From: Douglas H. <do...@do...> - 2015-02-11 20:20:32
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for posterity, both of my == operators are erroneous and should be replaced with .equals() On Wed, Feb 11, 2015 at 8:18 PM, Douglas Held <do...@do...> wrote: > Maybe I am just criminally insane, but I could solve my problem with the > following Java program. I would prefer however to learn to quickly use the > xml-coreutils command line utilities... > > import java.io.File; > import java.io.IOException; > import java.io.OutputStream; > import java.io.OutputStreamWriter; > > import javax.xml.parsers.DocumentBuilderFactory; > 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.w3c.dom.Element; > import org.w3c.dom.Node; > import org.w3c.dom.NodeList; > > > public class Search { > > public static void main(String[] args) throws Exception { > Document output = > DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument(); > output.appendChild( output.createElement( "listings" ) ); > System.out.println( output.getDocumentElement().toString() ); > > Document input = > DocumentBuilderFactory.newInstance().newDocumentBuilder().parse( new File( > "/Users/douglasheld/zoopla/listings.xml" ) ); > NodeList listings = input.getElementsByTagName( "listing" ); > for ( int i=0; i<listings.getLength(); i++ ){ > Node listing = listings.item( i ); > boolean insert = false; > Element newListing = output.createElement( "listing" ); > for ( int j=0; j < listing.getChildNodes().getLength(); j++){ > if ( listing.getChildNodes().item(j).getNodeName() == > "listing_id" ){ > newListing.setAttribute("id", > listing.getChildNodes().item(j).getFirstChild().getNodeValue() ); > } > if ( listing.getChildNodes().item(j).getNodeName() == > "floor_plan" ){ > insert = true; > Element newFloorPlan = output.createElement( > "floor_plan" ); > newFloorPlan.setTextContent( > listing.getChildNodes().item(j).getFirstChild().getNodeValue() ); > newListing.appendChild( newFloorPlan ); > } > } > if ( insert ){ > output.getDocumentElement().appendChild( newListing ); > System.err.print( '.' ); > } > } > printDocument( output, System.out ); > } > > /* copy/paste from > http://stackoverflow.com/questions/2325388/java-shortest-way-to-pretty-print-to-stdout-a-org-w3c-dom-document > */ > public static void printDocument(Document doc, OutputStream out) > throws IOException, TransformerException { > TransformerFactory tf = TransformerFactory.newInstance(); > Transformer transformer = tf.newTransformer(); > transformer.setOutputProperty(OutputKeys.OMIT_XML_DECLARATION, > "no"); > transformer.setOutputProperty(OutputKeys.METHOD, "xml"); > transformer.setOutputProperty(OutputKeys.INDENT, "yes"); > transformer.setOutputProperty(OutputKeys.ENCODING, "UTF-8"); > transformer.setOutputProperty("{ > http://xml.apache.org/xslt}indent-amount", "4"); > > transformer.transform(new DOMSource(doc), > new StreamResult(new OutputStreamWriter(out, "UTF-8"))); > } > } > > > On Wed, Feb 11, 2015 at 6:59 PM, Douglas Held <do...@do...> > wrote: > >> I need some help getting my thinking in the xml-coreutils world. >> >> I have some prepared data in the format: >> <response> >> <listing> >> <foo>foo</foo> >> <bar>bar</bar> >> <floor_plan>http://example.com/123456</floor_plan> >> <listing_id>1</listing_id> >> </listing> >> <listing> >> <listing_id>2</listing_id> >> <foo>foo</foo> >> <bar>bar</bar> >> </listing> >> </response> >> >> Each /response/listing element has a //listing_id and some, but not all >> listings have a floor_plan element. >> >> Goal: >> I would like to extract only listings with floor plans, and only the >> selected elements I am interested in, into a new document as: >> <listings> >> <listing> >> <listing_id>1</listing_id> >> <floor_plan>http://example.com/123456</floor_plan> >> </listing> >> <listings> >> >> I have tried commands such as: >> # Create the target file >> xml-echo -e "[listings@updated=20150210]" >listings.xml >> # Copy selected elements into target >> xml-cp page1.xml >> :/response/listing/listing_id[/response/listing/floor_plan != null] >> listings.xml :/listings/ >> >> I have read all the man pages and experimented with many different of the >> xml-* commands. Very seldom do they work as I am hoping. >> >> The workflow I would expect, based on the coreutils workflows I normally >> use, would be: >> cat source.xml | while read element; do >> if echo $element | grep -q floor_plan ; then >> echo $element >> target.xml >> fi >> done >> >> It would be nice if I could use a complement of the above technologies >> for processing the XML. The below are imaginary pseudo-commands: >> >> xml-cat source.xml :/response/listing | while xml-read listing; do >> # $listing is now an xml fragment of one listing element's full content >> if echo $listing | xml-grep -q ://floor_plan; then >> cat $element | xml-egrep >> "://listing|://listing/listing_id|://listing/floor_plan" | xml-insert >> target.xml :/listings/ >> fi >> done >> >> Perhaps by following my pseudo-logic, you can explain how I can carry out >> these operations with xml-coreutils. >> >> I have attached one of my source files. >> >> Regards, >> Doug >> -- >> Douglas Held >> do...@do... >> +447775733093 >> > > > > -- > Douglas Held > do...@do... > +447775733093 > -- Douglas Held do...@do... +447775733093 |