package org.superbiz.corn;
import javax.annotation.PostConstruct;
import javax.annotation.Resource;
import javax.ejb.Lock;
import javax.ejb.LockType;
import javax.ejb.ScheduleExpression;
import javax.ejb.Singleton;
import javax.ejb.Startup;
import javax.ejb.Timeout;
import javax.ejb.Timer;
import javax.ejb.TimerConfig;
import javax.ejb.TimerService;
import java.util.concurrent.atomic.AtomicInteger;
/**
* É aqui que programamos todos os trabalhos de milho do fazendeiro Brown(FarmerBrown)
*
* @version $Revision$ $Date$
*/
@Singleton
@Lock(LockType.READ) // permite que os temporizadores sejam executados em paralelo
@Startup
public class FarmerBrown {
private final AtomicInteger checks = new AtomicInteger();
@Resource
private TimerService timerService;
@PostConstruct
private void construct() {
final TimerConfig plantTheCorn = new TimerConfig("plantTheCorn", false);
timerService.createCalendarTimer(new ScheduleExpression().month(5).dayOfMonth("20-Last").minute(0).hour(8), plantTheCorn);
timerService.createCalendarTimer(new ScheduleExpression().month(6).dayOfMonth("1-10").minute(0).hour(8), plantTheCorn);
final TimerConfig harvestTheCorn = new TimerConfig("harvestTheCorn", false);
timerService.createCalendarTimer(new ScheduleExpression().month(9).dayOfMonth("20-Last").minute(0).hour(8), harvestTheCorn);
timerService.createCalendarTimer(new ScheduleExpression().month(10).dayOfMonth("1-10").minute(0).hour(8), harvestTheCorn);
final TimerConfig checkOnTheDaughters = new TimerConfig("checkOnTheDaughters", false);
timerService.createCalendarTimer(new ScheduleExpression().second("*").minute("*").hour("*"), checkOnTheDaughters);
}
@Timeout
public void timeout(Timer timer) {
if ("plantTheCorn".equals(timer.getInfo())) {
plantTheCorn();
} else if ("harvestTheCorn".equals(timer.getInfo())) {
harvestTheCorn();
} else if ("checkOnTheDaughters".equals(timer.getInfo())) {
checkOnTheDaughters();
}
}
private void plantTheCorn() {
// Escave o plantador !!!
}
private void harvestTheCorn() {
// Desenterre a colheitadeira !!!
}
private void checkOnTheDaughters() {
checks.incrementAndGet();
}
public int getChecks() {
return checks.get();
}
}
Schedule Expression (Cronograma Expressão)
Neste exemplo, exercitamos o TimerService
.
``A interface TimerService fornece componentes de bean corporativo com acesso ao serviço de cronômetro fornecido pelo contêiner. O EJB Timer Service permite que os beans de entidade, os beans de sessão sem estado e os beans controlados por mensagem sejam registrados para eventos de retorno de chamada do cronômetro em um tempo especificado, após um tempo decorrido especificado ou após um intervalo especificado.''
Para uma descrição completa do TimerService, consulte o tutorial Java EE dedicado ao Timer Service.
FarmerBrown
No PostConstruct
, criamos 5 temporizadores programáticos. Provavelmente, os quatro primeiros não serão acionados durante a execução do teste; no entanto, o último terá o tempo limite esgotado algumas vezes.
Cada cronômetro contém um atributo de informação, que pode ser inspecionado no tempo limite.
FarmerBrownTest
A classe de teste adquire uma instância do contexto e espera por 5 segundos para dar aos temporizadores uma chance de expirar.
package org.superbiz.corn;
import junit.framework.TestCase;
import javax.ejb.embeddable.EJBContainer;
import javax.naming.Context;
import static java.util.concurrent.TimeUnit.SECONDS;
/**
* @version $Revision$ $Date$
*/
public class FarmerBrownTest extends TestCase {
public void test() throws Exception {
final Context context = EJBContainer.createEJBContainer().getContext();
final FarmerBrown farmerBrown = (FarmerBrown) context.lookup("java:global/schedule-expression/FarmerBrown");
// Dê ao fazendeiro brown uma chance de fazer algum trabalho
Thread.sleep(SECONDS.toMillis(5));
final int checks = farmerBrown.getChecks();
assertTrue(checks + "", checks > 4);
}
}
Executando
-------------------------------------------------------
T E S T S
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Running org.superbiz.corn.FarmerBrownTest
Apache OpenEJB 4.0.0-beta-1 build: 20111002-04:06
http://tomee.apache.org/
INFO - openejb.home = /Users/dblevins/examples/schedule-expression
INFO - openejb.base = /Users/dblevins/examples/schedule-expression
INFO - Using 'javax.ejb.embeddable.EJBContainer=true'
INFO - Configuring Service(id=Default Security Service, type=SecurityService, provider-id=Default Security Service)
INFO - Configuring Service(id=Default Transaction Manager, type=TransactionManager, provider-id=Default Transaction Manager)
INFO - Found EjbModule in classpath: /Users/dblevins/examples/schedule-expression/target/classes
INFO - Beginning load: /Users/dblevins/examples/schedule-expression/target/classes
INFO - Configuring enterprise application: /Users/dblevins/examples/schedule-expression
WARN - Method 'lookup' is not available for 'javax.annotation.Resource'. Probably using an older Runtime.
INFO - Configuring Service(id=Default Singleton Container, type=Container, provider-id=Default Singleton Container)
INFO - Auto-creating a container for bean FarmerBrown: Container(type=SINGLETON, id=Default Singleton Container)
INFO - Configuring Service(id=Default Managed Container, type=Container, provider-id=Default Managed Container)
INFO - Auto-creating a container for bean org.superbiz.corn.FarmerBrownTest: Container(type=MANAGED, id=Default Managed Container)
INFO - Enterprise application "/Users/dblevins/examples/schedule-expression" loaded.
INFO - Assembling app: /Users/dblevins/examples/schedule-expression
INFO - Jndi(name="java:global/schedule-expression/FarmerBrown!org.superbiz.corn.FarmerBrown")
INFO - Jndi(name="java:global/schedule-expression/FarmerBrown")
INFO - Jndi(name="java:global/EjbModule481105279/org.superbiz.corn.FarmerBrownTest!org.superbiz.corn.FarmerBrownTest")
INFO - Jndi(name="java:global/EjbModule481105279/org.superbiz.corn.FarmerBrownTest")
INFO - Created Ejb(deployment-id=org.superbiz.corn.FarmerBrownTest, ejb-name=org.superbiz.corn.FarmerBrownTest, container=Default Managed Container)
INFO - Created Ejb(deployment-id=FarmerBrown, ejb-name=FarmerBrown, container=Default Singleton Container)
INFO - Started Ejb(deployment-id=org.superbiz.corn.FarmerBrownTest, ejb-name=org.superbiz.corn.FarmerBrownTest, container=Default Managed Container)
INFO - Started Ejb(deployment-id=FarmerBrown, ejb-name=FarmerBrown, container=Default Singleton Container)
INFO - Deployed Application(path=/Users/dblevins/examples/schedule-expression)
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 6.141 sec
Results :
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0