DeadlockProducerEJB.java

package com.oracle.example.utility;

import com.oracle.example.jms.Constants;
import weblogic.jms.extensions.WLConnection;
import weblogic.jms.extensions.WLMessageProducer;
import weblogic.jms.extensions.WLSession;

import javax.annotation.PostConstruct;
import javax.annotation.PreDestroy;
import javax.annotation.Resource;
import javax.ejb.LocalBean;
import javax.ejb.Stateless;
import javax.ejb.TransactionAttribute;
import javax.ejb.TransactionAttributeType;
import javax.jms.ConnectionFactory;
import javax.jms.JMSException;
import javax.jms.Queue;
import javax.jms.Session;
import java.io.Serializable;
import java.util.Date;
import java.util.logging.Logger;

/**
 * **************************************************************************
 * <p/>
 * This code is provided for example purposes only.  Oracle does not assume
 * any responsibility or liability for the consequences of using this code.
 * If you choose to use this code for any reason, including but not limited
 * to its use as an example you do so at your own risk and without the support
 * of Oracle.
 * <p/>
 * ****************************************************************************
 */
@Stateless(name = "DeadlockProducer", mappedName = "ejb/DeadlockProducer")
@LocalBean
public class DeadlockProducerEJB implements Serializable
{
  public static final String JMS_CF_JNDI = "com/oracle/example/jms/util/cf";
  public static final String JMS_QUEUE_JNDI = "com/oracle/example/jms/util/deadlock";

  private static final Logger logger = Logger.getLogger(DeadlockProducerEJB.class.getName());

  @Resource(name = JMS_CF_JNDI, type = ConnectionFactory.class)
  private ConnectionFactory connectionFactory;

  @Resource(name = JMS_QUEUE_JNDI, type = Queue.class)
  private Queue queue;

  private WLConnection connection;
  private WLSession session;
  private WLMessageProducer queueProducer;

  @PostConstruct
  public void initialize()
  {
    try
    {
      connection = (WLConnection) connectionFactory.createConnection();
      session = (WLSession) connection.createSession(false, Session.AUTO_ACKNOWLEDGE);
      queueProducer = (WLMessageProducer) session.createProducer(queue);
    }
    catch (JMSException e)
    {
      if (connection != null)
      {
        try
        {
          connection.close();
        }
        catch (JMSException f)
        {
          e.printStackTrace();
        }
      }
    }
  }

  @PreDestroy
  public void closeConnection()
  {
    try
    {
      if (connection != null)
      {
        connection.close();
      }
    }
    catch (JMSException e)
    {
      e.printStackTrace();
    }
  }

  @TransactionAttribute(TransactionAttributeType.NOT_SUPPORTED)
  public void doIt()
  {
    logger.info("Generating Deadlock!!!");
    int BATCH_SIZE = 4;

    try
    {
      for (int x = 0; x < BATCH_SIZE; x++)
      {
        logger.info("Sending message [ " + x + " / " + BATCH_SIZE + " ]");
        queueProducer.send(session.createTextMessage("Batch=[" + Constants.filenameDateFormatter.format(new Date()) + "] Hello World!! [ " + x + " / " + BATCH_SIZE + " ]"));
      }
    }
    catch (JMSException e)
    {
      e.printStackTrace();
    }

  }
}