OpenEdge Development:<br />Messaging and ESB Installing an error handler to handle an asynchronous error

The procedure example16.p (1 of 2) installs an error handler to detect a JMS server communication loss.

example16.p
/* Installs an error handler to deal with a JMS server communication loss. / DEFINE VARIABLE pubsubsession AS HANDLE. DEFINE VARIABLE errorConsumer AS HANDLE. DEFINE VARIABLE jmsIsOk AS LOGICAL INIT yes. RUN jms/pubsubsession.p PERSISTENT SET pubsubsession ("-H localhost -S 5162 "). RUN setBrokerURL IN pubsubsession ("localhost:2506"). RUN beginSession IN pubsubsession. RUN createMessageConsumer IN pubsubsession(THIS-PROCEDURE, "errorHandler", OUTPUT errorConsumer). RUN setErrorHandler IN pubsubsession (errorConsumer). RUN startReceiveMessages IN pubsubsession. / Wait forever for messages until the connection with the JMS server is lost with error code "-5" (shutdown the SonicMQ Broker to simulate that). */ RUN waitForMessages IN pubsubsession ("inWait", THIS-PROCEDURE, ?). IF NOT jmsIsOk THEN DO: MESSAGE "Disocnnectiong from JMS Server... "VIEW-AS ALERT-BOX. RUN deleteSession IN pubsubsession. END.
FUNCTION inWait RETURNS LOGICAL. RETURN jmsIsOk. END.
PROCEDURE errorHandler: DEFINE INPUT PARAMETER messageH AS HANDLE NO-UNDO. DEFINE INPUT PARAMETER messageConsumerH AS HANDLE NO-UNDO. DEFINE OUTPUT PARAMETER replyH AS HANDLE NO-UNDO. DEFINE VAR errorCode AS CHAR NO-UNDO. DEFINE VAR errorText AS CHAR NO-UNDO. ASSIGN errorCode = DYNAMIC-FUNCTION ('getCharProperty':U IN messageH, "errorCode") errorText = DYNAMIC-FUNCTION('getText':U IN messageH). RUN deleteMessage IN messageH. MESSAGE errorText errorCode VIEW-AS ALERT-BOX. IF errorCode = "-5" THEN jmsIsOk = no. END.

example16.p

/* Installs an error handler to deal with a JMS server communication loss. 
*/ 
DEFINE VARIABLE pubsubsession AS HANDLE. 
DEFINE VARIABLE errorConsumer AS HANDLE. 
DEFINE VARIABLE jmsIsOk AS LOGICAL INIT yes. 
RUN jms/pubsubsession.p PERSISTENT SET pubsubsession  
                                  ("-H localhost -S 5162 "). 
RUN setBrokerURL IN pubsubsession ("localhost:2506"). 
RUN beginSession IN pubsubsession. 
RUN createMessageConsumer IN pubsubsession(THIS-PROCEDURE,
                                           "errorHandler", 
                                           OUTPUT errorConsumer). 
RUN setErrorHandler IN pubsubsession (errorConsumer). 
RUN startReceiveMessages IN pubsubsession. 
/* Wait forever for messages until the connection with the JMS server is
   lost with error code "-5" (shutdown the SonicMQ Broker to simulate
   that). 
*/ 
RUN waitForMessages IN pubsubsession ("inWait", THIS-PROCEDURE, ?). 
IF NOT jmsIsOk THEN  
DO: 
    MESSAGE "Disocnnectiong from JMS Server... "VIEW-AS ALERT-BOX. 
    RUN deleteSession IN pubsubsession. 
END.

FUNCTION inWait RETURNS LOGICAL. 
    RETURN jmsIsOk. 
END.

PROCEDURE errorHandler: 
DEFINE INPUT PARAMETER messageH AS HANDLE NO-UNDO. 
DEFINE INPUT PARAMETER messageConsumerH AS HANDLE NO-UNDO. 
DEFINE OUTPUT PARAMETER replyH AS HANDLE NO-UNDO. 
DEFINE VAR errorCode AS CHAR NO-UNDO. 
DEFINE VAR errorText AS CHAR NO-UNDO. 
    ASSIGN
      errorCode = DYNAMIC-FUNCTION
        ('getCharProperty':U IN messageH, "errorCode") 
    errorText = DYNAMIC-FUNCTION('getText':U IN messageH). 
    RUN deleteMessage IN messageH. 
    MESSAGE errorText errorCode VIEW-AS ALERT-BOX. 
    IF errorCode = "-5" THEN 
        jmsIsOk = no. 
END.

Shut down the SonicMQ Broker to simulate the communication loss.