reserveofficemsgbean.java

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/*
 * Copyright (c) 2003 Sun Microsystems, Inc.  All rights reserved.  U.S.
 * Government Rights - Commercial software.  Government users are subject
 * to the Sun Microsystems, Inc. standard license agreement and
 * applicable provisions of the FAR and its supplements.  Use is subject
 * to license terms.
 *
 * This distribution may include materials developed by third parties.
 * Sun, Sun Microsystems, the Sun logo, Java and J2EE are trademarks
 * or registered trademarks of Sun Microsystems, Inc. in the U.S. and
 * other countries.
 *
 * Copyright (c) 2003 Sun Microsystems, Inc. Tous droits reserves.
 *
 * Droits du gouvernement americain, utilisateurs gouvernementaux - logiciel
 * commercial. Les utilisateurs gouvernementaux sont soumis au contrat de
 * licence standard de Sun Microsystems, Inc., ainsi qu'aux dispositions
 * en vigueur de la FAR (Federal Acquisition Regulations) et des
 * supplements a celles-ci.  Distribue par des licences qui en
 * restreignent l'utilisation.
 *
 * Cette distribution peut comprendre des composants developpes par des
 * tierces parties. Sun, Sun Microsystems, le logo Sun, Java et J2EE
 * sont des marques de fabrique ou des marques deposees de Sun
 * Microsystems, Inc. aux Etats-Unis et dans d'autres pays.
 */
package eb;

import java.rmi.RemoteException; 
import javax.rmi.PortableRemoteObject;
import javax.ejb.*;
import javax.naming.*;
import javax.jms.*;
import java.util.Random;

/**
 * The ReserveOfficeMsgBean class is a message-driven bean. It
 * implements the javax.ejb.MessageDrivenBean and 
 * javax.jms.MessageListener interfaces. It is defined as public 
 * (but not final or abstract).  It defines a constructor and the
 * methods ejbCreate, onMessage, setMessageDrivenContext, and
 * ejbRemove.
 */
public class ReserveOfficeMsgBean implements MessageDrivenBean, 
        MessageListener {

    private transient MessageDrivenContext mdc = null;
    private SetupOfficeLocalHome soLocalHome = null;
    private Random processingTime = new Random();
    
    /**
     * Constructor, which is public and takes no arguments.
     */
    public ReserveOfficeMsgBean() {
        System.out.println("In " +
            "ReserveOfficeMsgBean.ReserveOfficeMsgBean()");
    }

    /**
     * setMessageDrivenContext method, declared as public (but
     * not final or static), with a return type of void, and with
     * one argument of type javax.ejb.MessageDrivenContext.
     *
     * @param mdc    the context to set
     */
    public void setMessageDrivenContext(MessageDrivenContext mdc)
    {
        System.out.println("In " +
            "ReserveOfficeMsgBean.setMessageDrivenContext()");
        this.mdc = mdc;
    }

    /**
     * ejbCreate method, declared as public (but not final or
     * static), with a return type of void, and with no 
     * arguments. It looks up the entity bean and gets a handle
     * to its home interface.
     */
    public void ejbCreate() {
        System.out.println("In ReserveOfficeMsgBean.ejbCreate()");
        try {
            Context initial = new InitialContext();
            Object objref = 
                initial.lookup("java:comp/env/ejb/local/SetupOffice");
            soLocalHome = (SetupOfficeLocalHome)
                PortableRemoteObject.narrow(objref, 
                    SetupOfficeLocalHome.class);
        } catch (Exception ex) {
            System.err.println("ReserveOfficeMsgBean." +
                "ejbCreate: Exception: " + ex.toString());
        }
    }

    /**
     * onMessage method, declared as public (but not final or 
     * static), with a return type of void, and with one argument
     * of type javax.jms.Message.
     *
     * Casts the incoming Message to a MapMessage, retrieves its
     * contents, and assigns the new hire to an office. Calls the
     * compose method to store the information in the entity 
     * bean.
     *
     * @param inMessage    the incoming message
     */
    public void onMessage(Message inMessage) {
        MapMessage msg = null;
        String key = null;
        String name = null;
        String position = null;
        int officeNumber = 0;

        try {
            if (inMessage instanceof MapMessage) {
                msg = (MapMessage) inMessage;
                key = msg.getString("HireID");
                name = msg.getString("Name");
                position = msg.getString("Position");
                System.out.println("  ReserveOfficeMsgBean:" +
                    " Message received for employeeId " + key);
                
                officeNumber = new Random().nextInt(300) + 1;

                /* Simulate processing time taking 1 to 10 
                 * seconds.
                 */
                Thread.sleep(processingTime.nextInt(10) * 1000);
                compose(key, name, officeNumber, msg);
            } else {
                System.err.println("Message of wrong type: " + 
                    inMessage.getClass().getName());
            }
        } catch (JMSException e) {
            System.err.println("ReserveOfficeMsgBean." +
                "onMessage: JMSException: " + e.toString());
            mdc.setRollbackOnly();
        } catch (Throwable te) {
            System.err.println("ReserveOfficeMsgBean." +
                "onMessage: Exception: " + te.toString());
        }
    }
    
    /**
     * compose method, helper to onMessage method.
     *
     * Locates the row of the database represented by the primary
     * key and adds the office number allocated for the new hire.
     *
     * @param key           employee ID, primary key
     * @param name          employee name
     * @param officeNumber  office number
     * @param msg           the message received
     */
    void compose (String key, String name, int officeNumber, 
            Message msg) {
        int num = 0;
        SetupOfficeLocal so = null;

        try {
            so = soLocalHome.findByPrimaryKey(key);
            System.out.println("  ReserveOfficeMsgBean: " +
                "Found join entity bean for employeeId " +
                key);
        } catch (ObjectNotFoundException onfe) {
            System.err.println("No join entity bean found");
        } catch(FinderException fe) {
            mdc.setRollbackOnly();
        }

        // No entity bean found; create it
        if (so == null) {
           try {
               System.out.println("  ReserveOfficeMsgBean: " +
                   "Creating join entity bean for " +
                   "employeeId " + key);
               so = soLocalHome.createLocal(key, name); 
            } catch (CreateException e) {
                System.err.println("  ReserveOfficeMsgBean: " +
                    "Could not create join entity bean");
                mdc.setRollbackOnly();
            }
        }

        // Entity bean found or created, so add office
        if (so != null) {
            try {
                so.doOfficeNumber(officeNumber, msg);
            } catch(JMSException je) {
                System.err.println("  ReserveOfficeMsgBean: " +
                    "Could not get office");
                mdc.setRollbackOnly();
            }
        }
    }
    
    /**
     * ejbRemove method, declared as public (but not final or 
     * static), with a return type of void, and with no 
     * arguments.
     */
    public void ejbRemove() {
        System.out.println("In " +
            "ReserveOfficeMsgBean.ejbRemove()");
    }
}