Java/EJB3/Timer

EJB Tutorial from JBoss: timer

File: ExampleTimer.java
/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.tutorial.timer.bean;

public interface ExampleTimer
{
   void scheduleTimer(long milliseconds);
}

File: ExampleTimerBean.java
/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.tutorial.timer.bean;
import java.util.Date;
import javax.annotation.Resource;
import javax.ejb.Remote;
import javax.ejb.SessionContext;
import javax.ejb.Stateless;
import javax.ejb.Timeout;
import javax.ejb.Timer;
@Stateless
@Remote(ExampleTimer.class)
public class ExampleTimerBean implements ExampleTimer
{
   private @Resource SessionContext ctx;
   public void scheduleTimer(long milliseconds)
   {
      ctx.getTimerService().createTimer(new Date(new Date().getTime() + milliseconds), "Hello World");
   }
   @Timeout
   public void timeoutHandler(Timer timer)
   {
      System.out.println("---------------------");
      System.out.println("* Received Timer event: " + timer.getInfo());
      System.out.println("---------------------");
      timer.cancel();
   }
}

File: Client.java
/*
 * JBoss, Home of Professional Open Source.
 * Copyright 2006, Red Hat Middleware LLC, and individual contributors
 * as indicated by the @author tags. See the copyright.txt file in the
 * distribution for a full listing of individual contributors.
 *
 * This is free software; you can redistribute it and/or modify it
 * under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation; either version 2.1 of
 * the License, or (at your option) any later version.
 *
 * This software is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this software; if not, write to the Free
 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
 */
package org.jboss.tutorial.timer.client;
import org.jboss.tutorial.timer.bean.ExampleTimer;
import javax.naming.InitialContext;

public class Client
{
   public static void main(String[] args) throws Exception
   {
      InitialContext ctx = new InitialContext();
      ExampleTimer timer = (ExampleTimer) ctx.lookup("ExampleTimerBean/remote");
      timer.scheduleTimer(5000);
   }
}

Timer Service And Timeout Method

File: EmployeeBean.java
import javax.annotation.Resource;
import javax.ejb.SessionContext;
import javax.ejb.Stateless;
import javax.ejb.Timeout;
import javax.ejb.Timer;
import javax.ejb.TimerService;
@Stateless
public class EmployeeBean implements EmployeeServiceLocal, EmployeeServiceRemote {
  @Resource
  private SessionContext ctx;
  public EmployeeBean() {
  }
  public Long addBid(String userId, Long itemId, Double bidPrice) {
    System.out.println("Bid for " + itemId + " received with price" + bidPrice);
    TimerService timerService = ctx.getTimerService();
    Timer timer = timerService.createTimer(123, 86400000, null);
    return 0L;
  }
  @Timeout
  public void handleTimeout(Timer timer) {
    System.out.println(" handleTimeout called.");
    // Put here the code for cleaning the database of day limit orders that have
    // not been executed.
  }
}

File: EmployeeServiceLocal.java

import javax.ejb.Local;
import javax.jws.WebParam;
@Local
public interface EmployeeServiceLocal {
  public Long addBid(String userId,Long itemId,Double bidPrice);

}

File: EmployeeServiceRemote.java
import javax.ejb.Remote;

@Remote
public interface EmployeeServiceRemote {
  public Long addBid(String userId,Long itemId,Double bidPrice);
}

File: Employee.java

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.PostRemove;
@Entity
public class Employee implements java.io.Serializable {
  private int id;
  private String firstName;
  private String lastName;
  @Id
  @GeneratedValue
  public int getId() {
    return id;
  }

  @PostRemove
  public void postRemove()
  {
     System.out.println("@PostRemove");
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getFirstName() {
    return firstName;
  }
  public void setFirstName(String first) {
    this.firstName = first;
  }
  public String getLastName() {
    return lastName;
  }
  public void setLastName(String last) {
    this.lastName = last;
  }
}

File: Main.java
import javax.ejb.EJB;
import javax.naming.InitialContext;

public class Main {
  public static void main(String[] a) throws Exception {
    EmployeeServiceRemote service = null;
    // Context compEnv = (Context) new InitialContext().lookup("java:comp/env");
    // service = (HelloService)new
    // InitialContext().lookup("java:comp/env/ejb/HelloService");
    service = (EmployeeServiceRemote) new InitialContext().lookup("EmployeeBean/remote");

    service.addBid("userId",1L,0.1);
    

  }
}

File: jndi.properties
java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces
java.naming.provider.url=localhost:1099

Use Timer Service

File: Employee.java
import javax.persistence.Entity;
import javax.persistence.EntityListeners;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.PostRemove;
@Entity
public class Employee implements java.io.Serializable {
  private int id;
  private String firstName;
  private String lastName;
  @Id
  @GeneratedValue
  public int getId() {
    return id;
  }

  @PostRemove
  public void postRemove()
  {
     System.out.println("@PostRemove");
  }
  public void setId(int id) {
    this.id = id;
  }
  public String getFirstName() {
    return firstName;
  }
  public void setFirstName(String first) {
    this.firstName = first;
  }
  public String getLastName() {
    return lastName;
  }
  public void setLastName(String last) {
    this.lastName = last;
  }
}

File: EmployeeService.java
import java.util.Date;
import javax.annotation.Resource;
import javax.ejb.Stateless;
import javax.ejb.Timeout;
@Stateless
public class EmployeeService implements EmployeeServiceLocal, EmployeeServiceRemote {
  @Resource
  javax.ejb.TimerService timerService;
  public EmployeeService() {
  }
  public void doAction() {
    String item = "item 1";
    for (Object obj : timerService.getTimers()) {
      javax.ejb.Timer timer = (javax.ejb.Timer) obj;
      String scheduled = (String) timer.getInfo();
      if (scheduled.equals(item)) {
        timer.cancel();
      }
    }
    timerService.createTimer(new Date(System.currentTimeMillis() + 1000), item);
  }

  @Timeout
  public void maintenance(javax.ejb.Timer timer) {
    System.out.println("TIMEOUT METHOD CALLED");
    String scheduled = (String) timer.getInfo();
    System.out.println(scheduled);
  }
}

File: EmployeeServiceLocal.java

import java.util.Collection;
import javax.ejb.Local;
@Local
public interface EmployeeServiceLocal {
    public void doAction();
}

File: EmployeeServiceRemote.java


import java.util.Collection;
import javax.ejb.Remote;
@Remote
public interface EmployeeServiceRemote{
  public void doAction();  
}

File: jndi.properties
java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
java.naming.factory.url.pkgs=org.jboss.naming:org.jnp.interfaces
java.naming.provider.url=localhost:1099

File: Main.java
import java.util.Date;
import javax.naming.InitialContext;

public class Main {
  public static void main(String[] a) throws Exception {
    EmployeeServiceRemote service = null;
    // Context compEnv = (Context) new InitialContext().lookup("java:comp/env");
    // service = (HelloService)new InitialContext().lookup("java:comp/env/ejb/HelloService");
    service = (EmployeeServiceRemote) new InitialContext().lookup("EmployeeService/remote");
    
    

    
    service.doAction();
  }
}