package dataqueue;

import java.beans.PropertyChangeListener;

import java.beans.PropertyChangeSupport;

import com.ibm.as400.access.AS400;

import com.ibm.as400.access.ConnectionDroppedException;

import com.ibm.as400.access.KeyedDataQueue;

import com.ibm.as400.access.KeyedDataQueueEntry;

import com.ibm.as400.access.Record;

import com.ibm.as400.access.RecordFormat;

import common.MDLOFMFormat;

import common.Me;

/**

* Read the model output data queue. The AS400 object and the key to read was

* passed to the constructor of the class when instantiated. The IFS path of the

* model output data queue is read from Me class. Disconnecting the DATAQUEUE

* service of the AS400 object causes and exception and ends the exection of the

* thread. Any unexpected AS400 exceptions also end the execution of the thread

* after printing a stack trace.

*

* @author Bill Blalock

*

*/

public class DtaQExample3Thread extends Thread {

/**

* Key of model data queue for read, passed to the class when instantiated.

*/

private String KEY;

/**

* AS400 object to be passed to the class when instantiated.

*/

private AS400 as400 = null;

final PropertyChangeSupport pcs = new PropertyChangeSupport(this);

// don't allow default constructor

private DtaQExample3Thread() {

};

/**

* Constructor of thread to listen to model output data queue.

*

* @param as400

* Instance of AS400 provided by creator of thread.

* @param KEY

* Value of key to listen for.

*/

DtaQExample3Thread(AS400 as400, String KEY) {

this.as400 = as400;

this.KEY = KEY;

}

/**

* Read the model output data queue. The AS400 object and the key to

* read was passed to the constructor of the class when instantiated.

* The IFS path of the model output data queue is read from Me class.

* Disconnecting the DATAQUEUE service of the AS400 object causes and

* exception and ends the exection of the thread. Any unexpected AS400

* exceptions also end the execution of the thread after printing a

* stack trace.

*/

public void run() {

RecordFormat mdloFormat = new MDLOFMFormat();

try {

// connect to data queue

KeyedDataQueue mdloDq = new KeyedDataQueue(as400, Me.getMDLO_DTAQ());

Record mdloData = null;

Record oldMdloData = null;

// this loop won't end unless an Exception occurs or the JVM is ended

while (true) {

// Wait for the model response.

KeyedDataQueueEntry mdloDataQueueEntry = mdloDq.read(KEY, 3600, "EQ");

// Using a wait of -1 is easier programming, you don't need to

// handle time out. This is okay for short lived program but

// not for long life programs. If the data queue service

// failed on the System i, say the system was IPL'd, the program

// waiting forever would never see the interruption.

if (mdloDataQueueEntry == null) {

System.out

.println("... the model took too long to respond ... ");

continue;

}

// We just read an entry off the queue. Put the data into

// a Record object so the program can access the fields of

// the data by name. The Record object will also convert

// the data from server format to Java format.

mdloData = mdloFormat

.getNewRecord(mdloDataQueueEntry.getData());

// Pass the record object to the property change listener.

this.pcs.firePropertyChange("dqRead", oldMdloData, mdloData);

// save the record object just read as the old record object

oldMdloData = mdloData;

} // end of while(true)

} catch (ConnectionDroppedException e) {

// drop connection okay -- main() drops the connection before

// exiting ... that will cause the KeyedDataQueue.read() method to

// fail

System.out.println("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");

System.out

.println("The rug has been pulled out from under the data queue reading thread!!!");

System.out.println("The thread has been forced to end.");

System.out.println("!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!");

} catch (InterruptedException e) {

System.out.println("InterruptedException: " + e.getMessage());

} catch (Exception e) {

// If any of the above operations failed say the data queue

// operation

// failed and output the exception.

if (as400 != null)

as400.disconnectAllServices();

System.out.println("Data Queue operation failed");

System.out.println(e);

e.printStackTrace();

if (as400 != null)

if (as400.isConnected())

as400.disconnectAllServices();

System.exit(0);

}

}

/**

* Add a PropertyChangeListener for bound property using the services of the

* PropertyChangeSupport class.

* @param listener

*/

public void addPropertyChangeListener(PropertyChangeListener listener) {

this.pcs.addPropertyChangeListener(listener);

}

/**

* Remove a PropertyChangeListener using the services of the

* PropertyChangeSupport class.

* @param listener

*/

public void removePropertyChangeListener(PropertyChangeListener listener) {

this.pcs.removePropertyChangeListener(listener);

}

}