Setting up an XQJ DataSource

Choosing an XQJ Datasource, but which XQJ Vendor?

There are quite a few implementations of XQJ out there. To keep things simple, let's pick a free open source Native XML Database with an XQJ Driver, like the Sedna XML Database.

1. Download, install and start the XML Database

Goto Sedna's website (http://www.modis.ispras.ru/sedna/) and download the latest and greatest version of the Sedna XML database for your operating system.

* For Linux there should be an executable installer which looks like sedna-x.x.x-bin-linux-i686.sh
* For Windows there should be a gzipped tar archive which looks like sedna-x.x.x-bin-win.tar.gz, you will need to extract this file somewhere, it will extract to a directory called 'sedna'.

Once you have downloaded and installed (or extracted) the Sedna XML Database binaries, it's time to create and run a Database called 'test'.

In a console/shell, navigate to your Sedna installation root directory, i.e. 'sedna' and execute:

Linux:

[user@sedna ~]# cd bin
[user@bin ~]# se_gov
GOVERNOR has been started in the background mode

[user@bin ~]# se_cdb test
Creating a data base (it can take a few minutes)...
The database 'test' has been created successfully

[user@bin ~]# se_sm test
Starting database recovery or hot-backup restoration...
Database is in consistent state. Starting...
SM has been started in the background mode

Windows:

C:\path\to\sedna> cd bin
C:\path\to\sedna\bin> se_gov
GOVERNOR has been started in the background mode

C:\path\to\sedna\bin> se_cdb test
Creating a data base (it can take a few minutes)...
The database 'test' has been created successfully

C:\path\to\sedna\bin> se_sm test
Starting database recovery or hot-backup restoration...
Database is in consistent state. Starting...
SM has been started in the background mode

2. Get some data

To perform XQueries, ideally we need some data to query against, so let's get some XML data and load it into our database instance.

Take the following file and save it to the 'src' directory on your hard-disk

books.xml

<?xml version="1.0"?> <catalog> <book isbn="0470192747"> <author>Kay, Michael</author> <title>XSLT 2.0 and XPath 2.0 (4th Edition)</title> <genre>Computer</genre> <price>33.99</price> <publish_date>2008-06-03</publish_date> <description>This book is primarily a practical reference book for professional XSLT developers.</description> </book> <book isbn="0596006349"> <author>Walmsley, Priscilla</author> <title>XQuery</title> <genre>Computer</genre> <price>38.50</price> <publish_date>2007-03-30</publish_date> <description>This in-depth tutorial not only walks you through the XQuery specification, but also teaches you how to program with this widely anticipated query language.</description> </book> <book isbn="059652112X"> <author>Kalin, Martin</author> <title>Java Web Services: Up and Running</title> <genre>Computer</genre> <price>26.99</price> <publish_date>2009-02-23</publish_date> <description>With this example-driven book, you get a quick, practical, and thorough introduction to Java's API for XML Web Services (JAX-WS) and the Java API for RESTful Web Services (JAX-RS).</description> </book> <book isbn="0321356683"> <author>Bloch, Joshua</author> <title>Effective Java (2nd Edition)</title> <genre>Computer</genre> <price>35.99</price> <publish_date>2008-05-22</publish_date> <description>Presents the most practical, authoritative guidelines available for writing efficient,well-designed programs.</description> </book> <book isbn="0141014865"> <author>de Botton, Alain</author> <title>Status Anxiety</title> <genre>Philosophy</genre> <price>9.99</price> <publish_date>2005-01-13</publish_date> <description>The author presents a universal condition of which many of us suffer from called Status Anxiety, investigates it's origins and possible solutions.</description> </book> <book isbn="0201771861"> <author>Rusty Harold, Elliotte</author> <title>Processing XML with Java (SAX, DOM, JDOM, JAXP &amp; TrAX)</title> <genre>Computer</genre> <price>37.99</price> <publish_date>2002-11-14</publish_date> <description>Handing and processing XML in the Java programming language.</description> </book> <book isbn="1887521143"> <author>Poomsan Becker, Benjawan</author> <title>Thai-English and English-Thai Dictionary</title> <genre>Dictionary</genre> <price>14.95</price> <publish_date>2005-04-30</publish_date> <description>With Transliteration for Non-Thai Speakers - Complete with Thai Alphabet Guide</description> </book> <book isbn="0415071771"> <author>Jung, Carl Gustav</author> <title>Psychological Types</title> <genre>Psychology</genre> <price>19.99</price> <publish_date>1992-01-02</publish_date> <description>Essential reading for anyone requiring a proper understanding of Jung's psychology, this was the work in which Jung set out his theory of psychological types as a means of understanding ourselves and the world around us.</description> </book> <book isbn="0596003552"> <author>Pawson, Dave</author> <title>XSL-FO: Making XML Look Good in Print</title> <genre>Computer</genre> <price>26.99</price> <publish_date>2002-08-19</publish_date> <description>Outlines XSL FO's strengths and weaknesses, provides a tutorial and reference guide.</description> </book> <book isbn="0321392795"> <author>Gray, Simon</author> <title>Data Structures in Java</title> <genre>Computer</genre> <price>53.99</price> <publish_date>2006-11-13</publish_date> <description>From Abstract Data Types to the Java Collections Framework.</description> </book> </catalog>

In a console/shell, navigate to your Sedna installation root directory, i.e. 'sedna' and execute:

Linux: (Replace '/path/to/src' with the path to your 'src' directory)

[user@sedna ~]# cd bin
[user@bin ~]# se_term -query "LOAD '/path/to/src/books.xml' 'books.xml'" test
Bulk load succeeded

Windows: (Replace 'c:\path\to\src' with the path to your 'src' directory)

C:\path\to\sedna> cd bin
C:\path\to\sedna\bin> se_term -query ^
"LOAD 'c:\path\to\src\books.xml' 'books.xml'" test

Bulk load succeeded

That's all the database setup out of the way.

3. Downloading the XQJ Implementation

We will need to create a directory on your hard-disk which will contain example Java sources from this tutorial and the XQJ jar library which they will depend on.

Create a directory on your hard-disk called 'src'.

The binary jar file containing the javax.xml.xquery interfaces and the Sedna XQJ implementation can be found here. Download this and make sure that all source from this tutorial can find it on the classpath when compiling and executing.

4. Get yourself connected

Save the following file to the 'src' directory.

ConnectAndDisconnect.java

import javax.xml.xquery.*; import net.cfoster.sedna.xqj.SednaXQDataSource;