Re: Differences between calling Java from Qshell and RPG?

"McCully, Keith (RBS Insurance)" wrote:

There are two reasons that I'm using Java over RPG to send MQ messages:

1. There's a requirement to attach several .pdf docs to the message. I don't
believe this can be done via the RPG APIs.
2. Another development team here already had a set of message and attachment
classes so I was able to put a wrapper around them.

Another way for RPG to talk to Java is through data queues.  This way
usually outperforms the direct RPG<->Java calling through JNI, and has
none of the problems that RPG->Java can experience with the JVM setup. 
The worst problem with RPG->Java is that there is only one JVM per job,
and if it gets started before all the environment variables are setup,
there's no way to recover in that job.

Neverending Java job which can be started by the QSH java command: 
 loop
 {
   get request from data queue A
   process
   put reply on data queue B
 }

RPG program:
   put request to data queue A
   receive reply from data queue B