RE: JCA Error

[Lucas José <lucas_5639@hotmail.com>]

Thank you Mark,

But now, I got this error "gov.aps.jca.CAException: Unable to create context", and looking on code of JCA, I found this: "@exception CAException is thrown if the context could not be instanciated. ", but I don't found why could not be instanciated.

Thanks,
Lucas José.

---

From: rivers@cars.uchicago.edu
To: lucas_5639@hotmail.com; tech-talk@aps.anl.gov
Subject: RE: JCA Error
Date: Thu, 28 Feb 2013 16:18:31 +0000

You are using the Java Native Interface (JNI) which requires a shareable library on your host.  What happens if you use the pure-Java interface by using this call instead:

 

   ctx=jca.createContext(JCALibrary.CHANNEL_ACCESS_JAVA);

 

Mark

 

 

From: tech-talk-bounces@aps.anl.gov [mailto:tech-talk-bounces@aps.anl.gov] On Behalf Of Lucas José
Sent: Thursday, February 28, 2013 9:48 AM
To: tech-talk@aps.anl.gov
Subject: JCA Error

 

Hello, all

I'm trying to execute the simple example using JCA, to implement a channel access client in Java, but doesn't work.

    The main function of my class (SimpleJCAGet):
    
    (...)

    SimpleJCAGet simpleJCAGet = new SimpleJCAGet();
    JCALibrary jca=null;
    Context ctxt=null;
    Channel chan=null;

    if(!simpleJCAGet.parseCommand(args)) System.exit(1);
    if(!simpleJCAGet.pvSpecified) {
      System.err.println("No PV specified\n");
      System.exit(1);
    }


    try {

      jca=JCALibrary.getInstance();

      ctxt=jca.createContext(JCALibrary.JNI_SINGLE_THREADED);
      chan=ctxt.createChannel(simpleJCAGet.name);
      ctxt.pendIO(simpleJCAGet.timeout);
    
    } catch(Exception ex) {
      System.err.println(ex);
      System.exit(1);
    }

    (...)

In this point (chan=ctxt.createChannel(simpleJCAGet.name)), he throws an exception: "java.lang.IllegalStateException: Context not initialized".

The doc ( http://www.aps.anl.gov/bcda/jca/jca/2.1.2/api/gov/aps/jca/Context.html#createChannel%28java.lang.String%29 ) says: "    java.lang.IllegalStateException - if the context has been destroyed." , but the context was created in the previous row.

The files are correct, the IOC is running corretly, and this example is in page of JCA. What could be wrong?

Thanks (And sorry my english)!
Lucas José