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Wrap the Result of an XQuery Query into an XML Document

Wrap the Result of an XQuery Query into an XML Document

Wrapping the result of an XQuery query into an XML document is very useful if you’re working with atomic values. The following Java program uses the net.sf.saxon.om.SequenceIterator and net.sf.saxon.query.QueryResult classes to do this:

/*The resulted document : C:Data_Localxmldocswrap.xml*///Javaimport java.io.File;import java.io.OutputStream;import java.io.FileOutputStream;import java.util.Properties;import javax.xml.transform.OutputKeys;import javax.xml.transform.stream.StreamResult;//Saxonimport net.sf.saxon.om.SequenceIterator;import net.sf.saxon.query.QueryResult;import net.sf.saxon.om.DocumentInfo;import net.sf.saxon.Configuration;import net.sf.saxon.query.DynamicQueryContext;import net.sf.saxon.query.StaticQueryContext;import net.sf.saxon.query.XQueryExpression;public class XQueryWrapExample {   public static void main(String[] args) {            XQueryExpression exp=null; //used for compilation                   //the XQuery query      String query="for $i in (1, 2,3)"+"return ($i)";                      //wrap.xml      String xmlFileName="C://Data_Local//xml//docs//wrap.xml";      File outFile=null;            OutputStream destStream=null;                                       //create an instance of Configuration      Configuration C=new Configuration();              //create the static and dynamic contexts      StaticQueryContext SQC=new StaticQueryContext(C);      DynamicQueryContext DQC=new DynamicQueryContext(C);                    //indentation      Properties props=new Properties();      props.setProperty(OutputKeys.METHOD,"xml");      props.setProperty(OutputKeys.INDENT,"yes");      try{         //"prepare" the wrap.xml         outFile=new File(xmlFileName);                    destStream=new FileOutputStream(outFile);         //compile the XQuery query         exp=SQC.compileQuery(query);         SQC=exp.getStaticContext();          }catch(net.sf.saxon.trans.XPathException e)            {System.err.println(e.getMessage());         }catch(java.io.IOException e)            {System.err.println(e.getMessage());}                try{                       //execute the query and wrap the result into wrap.xml         SequenceIterator SI=exp.iterator(DQC);          DocumentInfo DI=QueryResult.wrap(SI,C);          QueryResult.serialize(DI,new                          StreamResult(destStream),props,C);          destStream.close();         }catch(net.sf.saxon.trans.XPathException e)            {System.err.println(e.getMessage());         }catch(java.io.IOException e)            {System.err.println(e.getMessage());}                                }   }Result:<?xml version="1.0" encoding="UTF-8"?>   1   2   3
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