Here, the XML document is named as courses.xml and xqy file is named as courses.xqy
courses.xml
<?xml version="1.0" encoding="UTF-8"?> <courses> <course category="JAVA"> <title lang="en">Learn Java in 3 Months.</title> <trainer>Sonoo Jaiswal</trainer> <year>2008</year> <fees>10000.00</fees> </course> <course category="Dot Net"> <title lang="en">Learn Dot Net in 3 Months.</title> <trainer>Vicky Kaushal</trainer> <year>2008</year> <fees>10000.00</fees> </course> <course category="C"> <title lang="en">Learn C in 2 Months.</title> <trainer>Ramesh Kumar</trainer> <year>2014</year> <fees>3000.00</fees> </course> <course category="XML"> <title lang="en">Learn XML in 2 Months.</title> <trainer>Ajeet Kumar</trainer> <year>2015</year> <fees>4000.00</fees> </course> </courses>
courses.xqy
for $x in doc("courses.xml")/courses/course where $x/fees>5000 return $x/title
This example will display the title elements of the courses whose fees are greater than 5000.
Create a Java based XQuery executor program to read the courses.xqy, passes it to the XQuery expression processor, and executes the expression. After that the result will be displayed.
XQueryTester.java
import java.io.File; import java.io.FileInputStream; import java.io.FileNotFoundException; import java.io.InputStream; import javax.xml.xquery.XQConnection; import javax.xml.xquery.XQDataSource; import javax.xml.xquery.XQException; import javax.xml.xquery.XQPreparedExpression; import javax.xml.xquery.XQResultSequence; import com.saxonica.xqj.SaxonXQDataSource; public class XQueryTester { public static void main(String[] args){ try { execute(); } catch (FileNotFoundException e) { e.printStackTrace(); } catch (XQException e) { e.printStackTrace(); } } private static void execute() throws FileNotFoundException, XQException{ InputStream inputStream = new FileInputStream(new File("courses.xqy")); XQDataSource ds = new SaxonXQDataSource(); XQConnection conn = ds.getConnection(); XQPreparedExpression exp = conn.prepareExpression(inputStream); XQResultSequence result = exp.executeQuery(); while (result.next()) { System.out.println(result.getItemAsString(null)); } } }
Put the above three files to a same location. We put them on desktop in a folder name XQuery2. Compile XQueryTester.java using console. You must have JDK 1.5 or later installed on your computer and classpaths are configured.
Compile:
javac XQueryTester.java
Execute:
java XQueryTester
Output: