The default connection pool and multiple components in IBM MQ classes for Java

This example shows how to add or remove MQPoolTokens from a static set of registered MQPoolToken objects.

MQEnvironment holds a static set of registered MQPoolToken objects. To add or remove MQPoolTokens from this set, use the following methods:

• MQEnvironment.addConnectionPoolToken()
• MQEnvironment.removeConnectionPoolToken()

An application might consist of many components that exist independently and perform work using a queue manager. In such an application, each component should add an MQPoolToken to the MQEnvironment set for its lifetime.

For example, the example application MQApp3 creates ten threads and starts each one. Each thread registers its own MQPoolToken, waits for a length of time, then connects to the queue manager. After the thread disconnects, it removes its own MQPoolToken.

The default connection pool remains active while there is at least one token in the set of MQPoolTokens, so it will remain active for the duration of this application. The application does not need to keep a master object in overall control of the threads.

import com.ibm.mq.*;
public class MQApp3
{
      public static void main(String[] args)
      {
         for (int i=0; i<10; i++) {
            MQApp3_Thread thread=new MQApp3_Thread(i*60000);
            thread.start();
      }
}

class MQApp3_Thread extends Thread
{
      long time;

      public MQApp3_Thread(long time)
      {
         this.time=time;
      }

      public synchronized void run()
      {
         MQPoolToken token=MQEnvironment.addConnectionPoolToken();
         try {	
            wait(time);
            MQQueueManager qmgr=new MQQueueManager("my.qmgr.1");
            :
            : (do something with qmgr)
            :
            qmgr.disconnect();
         catch (MQException mqe) {System.err.println("Error occurred!");}
         catch (InterruptedException ie) {}

         MQEnvironment.removeConnectionPoolToken(token);
      }
}

Parent topic: Connection pooling in IBM MQ classes for Java