Update.... Great news! The JDBC driver for Jena will work fine in Teiid!!!! (thanks again for your help, Rob/Andy)
Ramesh noticed something from my comment and I noticed something from his: https://developer.jboss.org/message/965015?tstart=0#965015 Perhaps the Teiid team could include this in their next release so that it would support the JENA JDBC driver out of the box, would make it easier for others to take advantage of all of this great work. -----Original Message----- From: [email protected] [mailto:[email protected]] Sent: Thursday, November 03, 2016 9:16 PM To: [email protected] Subject: RE: JDBC in Teiid/JBoss NodeValue / ClassNotFounderror Rob/Andy - I added more to this thread, I was able to create a simple Java program and query a triplestore - to gain a better understanding of the JDBC driver outside of Teiid, could either of you take a look at the bottom of this thread and add some colour? I'm not sure what guidance to give to Ramesh to help bridge the gap: https://developer.jboss.org/thread/272656 I think this is an excellent opportunity to get an open-source data virtualization working with semantics and think there are some interesting possibilities for combining data in this manner. I really appreciate you both helping out with this. I see it as a way to build views on to SPARQL and vice versa and believe it would help further with adoption within large organizations that have legacy RDBMSs ; I've already leveraged Teiid on the Ontop to perform federated queries from r2rml to create materialized RDF in a really easy way, and this flexibility would just pile on to that. -----Original Message----- From: [email protected] [mailto:[email protected]] Sent: Wednesday, November 02, 2016 12:16 PM To: [email protected] Subject: RE: JDBC in Teiid/JBoss NodeValue / ClassNotFounderror Rob - I restarted and tried much of the below , but same behavior - Ramesh has just responded with a question here at the bottom of the thread: https://developer.jboss.org/thread/272656 -----Original Message----- From: Rob Vesse [mailto:[email protected]] Sent: Wednesday, November 02, 2016 11:16 AM To: [email protected] Subject: Re: JDBC in Teiid/JBoss NodeValue / ClassNotFounderror One possibility is that there is JAR/class caching going on. You may need to completely remove your application from JBoss and then redeploy it as the fact that you still see this behaviour implies that you still aren’t getting the correct services files from the JAR files. Restart of the container/JVM may also be necessary Note that if you choose to use the individual driver JAR files then you would need to also add all the dependencies explicitly as that could also lead to missing classes and initialisations Rob On 02/11/2016 13:19, "[email protected]" <[email protected]> wrote: Rob/Andy - thanks! I'm not sure if I made this clear ... My query does work fine as long as I don't include "FILTER"; I'm able to get back a select ?s ?p ?o {?s ?p ?o} with no issues from the driver I did just try the latest snapshot bundle jar, unfortunately... If I include FILTER regex(?var,"value") I still get: Caused by: java.lang.NoClassDefFoundError: Could not initialize class org.apache.jena.sparql.expr.NodeValue I don't believe Teiid is doing any repackaging, and I'm also confused if I include the individual jar files it won't work .. Anything else I could try to troubleshoot this? I'm at a loss -----Original Message----- From: Rob Vesse [mailto:[email protected]] Sent: Wednesday, November 02, 2016 6:00 AM To: [email protected] Subject: Re: JDBC in Teiid/JBoss NodeValue / ClassNotFounderror They seem to be conflating two different things here We do use and support Standard JDBC Driver initialisation. We also use the same underlying Java mechanism i.e. ServiceLoader to initialise Jena itself. Our JDBC driver initialisation invokes our Jena initialisation. So as far as we’re concerned we are not doing anything wrong: https://github.com/apache/jena/blob/master/jena-jdbc/jena-jdbc-driver-remote/src/main/java/org/apache/jena/jdbc/remote/RemoteEndpointDriver.java#L178 https://github.com/apache/jena/blob/master/jena-jdbc/jena-jdbc-driver-tdb/src/main/java/org/apache/jena/jdbc/tdb/TDBDriver.java#L95 https://github.com/apache/jena/blob/master/jena-jdbc/jena-jdbc-driver-mem/src/main/java/org/apache/jena/jdbc/mem/MemDriver.java#L90 As Andy has pointed out there was a bug in how the bundle JAR with all the drivers was being created which meant that Jena initialisation wasn’t happening properly because the composites services file for Jena initialisers wasn’t being created properly. If you use the latest 3.1.1-SNAPSHOT builds then this is resolved. lists.apache.org provides a much more modern interface to our mailing lists Rob On 02/11/2016 03:10, "[email protected]" <[email protected]> wrote: Hi Andy - further info from Ramesh ; thanks for your patience - he was having access accessing /reading MarkMail - so I'm relaying (original from bottom of https://developer.jboss.org/thread/272656) : "Basically what they need to do, replace their ServiceLoader mechanism with standard JDBC4 ServiceLoader mechanism like https://github.com/rareddy/teiid/tree/master/client/src/main/resources/META-INF/services That will register their Driver class, and in their driver class possibly in a "static block" call ARQ.init() that will initialize every time one uses their JDBC driver. " -----Original Message----- From: Andy Seaborne [mailto:[email protected]] Sent: Tuesday, November 01, 2016 12:10 PM To: [email protected] Subject: Re: JDBC in Teiid/JBoss NodeValue / ClassNotFounderror On 01/11/16 14:54, [email protected] wrote: > Thanks Andy! > > Question - who is responsible for loading the JDBC driver, and how does one load it? > > I'm not clear on exact details on how to get it to work. I reached out to the Teiid team, and Ramesh has a question for you . > > Can you look at the bottom of this thread for the question from Ramesh? > > https://developer.jboss.org/thread/272656 Firstly - I didn't write and don't use jena-jdbc so my level of expertise is limited. The initialization of Jena in shaded jars is something that has come up before. It looks like the problem is at the Jena initialization step, not the loading the JDBC driver. That's supposed to be automatic and is - the crash happens because the initialization is incomplete or is happening in the wrong order because the normal sequence isn't happening. In yoru code, if you can, call ARQ.init() before anything else. Calling it repeatedly is safe and cheap. Hopefully RobV can give a better answer for the JDBC aspects. There is a services/java.sql.Driver - that should cause the JDBC driver to load. Standard way for Java. Andy > > > -----Original Message----- > From: Andy Seaborne [mailto:[email protected]] > Sent: Tuesday, November 01, 2016 5:49 AM > To: [email protected] > Subject: Re: JDBC in Teiid/JBoss NodeValue / ClassNotFounderror > > >> I checked and the jena-jdbc-driver-bundle does not set up the >> ServiceLoader services correctly. We'll fix that. > > jena-jdbc-driver-bundle should be fixed (JENA-1255) now. There is a development with it in. > > Andy > >> >> But I don't immediately see why using the jars directly does not >> work, but that's due to my lack of knowledge about Teiid and JBoss. >> >> Is there any repackaging going on? >> >> Andy >
