wayne

1. 屬性有name, mappedName, description
2. name屬性用來指定bean的name, 有的container用來和JNDI綁定. 如果name沒有設定就會是bean的class name.
3. mappedName是vender-specific(特定于廠商), 也就是依不同container有不同的情形. 以GlassFish來說是將mappedName的值綁定到JNDI name.

1. 一個@Remote interface可以繼承java.rmi.Remote

    public interface TestRemote extends Remote { ... } 

   就算程序裡面沒寫繼承Remote, container還是會在byte code階段插入繼承Remote的動作
2. 沒有程序上繼承java.rmi.Remote的好處就是不用處理java.rmi.RemoteException
3. @Remote business interface有個需求就是所有的參數與回傳值都必須是Serializable, 因為這樣才能通過RMI

@Stateful(name="SimpleStatefulBean", mappedName="ejb/SimpleStatefulBean")
public class SimpleStatefulBean implements SimpleStatefulRemote {
private Logger logger = Logger.getLogger("SimpleStatefulBean");
private byte[] b = new byte[100000];
{
for ( int i = 0; i < b.length; i++ ) {
b[i] = (byte) 100;
}
}
public String simpleShow() {
return this + ":This is simple show" + b;
}
@PostConstruct
public void postConstruct() {
logger.info("create " + this);
}
@PreDestroy
public void preDestroy() {
logger.info("destroy " + this);
}
@PostActivate
public void postActivate() {
logger.info("activate " + this);
}
@PrePassivate
public void prePassivate() {
logger.info("passivate " + this);
}
@Remove
public void remove() {
logger.info("remove " + this);
}
}

@Stateless
@Interceptors(value={SimpleInterceptor.class})
public class SimpleStatelessBean implements SimpleStatelessLocal {
private Logger logger = Logger.getLogger("SimpleStatelessBean");
@Resource(name="TestQueueConnectionFactory")
private ConnectionFactory connectionFactory;
@Resource(name="jms/TestQueueDestination")
private Destination destination;
public String simpleShow() {
try {
Connection conn = connectionFactory.createConnection();
Session session = conn.createSession(false, Session.AUTO_ACKNOWLEDGE);
MessageProducer messageProducer = session.createProducer(destination);
TextMessage message = session.createTextMessage();
message.setText("This is text message");
messageProducer.send(message);
messageProducer.close();
session.close();
conn.close();
} catch (JMSException ex) {
throw new RuntimeException( ex );
}
return this + ":This is simple show";
}
}
public class SimpleInterceptor {
Logger logger = Logger.getLogger("SimpleStatefulBeanInterceptor");
@PostConstruct
public void onCreate(InvocationContext ic) {
try {
logger.info("create " + this);
ic.proceed();
} catch (Exception ex) {
Logger.getLogger(SimpleInterceptor.class.getName()).log(Level.SEVERE, null, ex);
}
}
@AroundInvoke
public Object aroundInvoke(InvocationContext ctx) throws Exception {
logger.info(ctx + " is invoked.");
return ctx.proceed();
}
@PreDestroy
public void onDestroy(InvocationContext ic) {
try {
logger.info("destroy " + this);
ic.proceed();
} catch (Exception ex) {
Logger.getLogger(SimpleInterceptor.class.getName()).log(Level.SEVERE, null, ex);
}
}
}

@Interceptors(value={SimpleInterceptor.class})

@Stateful(name="SimpleStatefulBean", mappedName="ejb/SimpleStatefulBean")
public class SimpleStatefulBean implements SimpleStatefulRemote {
private byte[] b = new byte[100000];
{
for ( int i = 0; i < b.length; i++ ) {
b[i] = (byte) 100;
}
}
public String simpleShow() {
return this + ":This is simple show" + b;
}
@Remove
public void remove() {
Logger.getLogger("SimpleStatefulBean").info("remove " + this);
}
}
public class SimpleInterceptor {
@PostConstruct
public void onCreate(InvocationContext ic) {
try {
Logger.getLogger(SimpleInterceptor.class.getName()).info("create " + this);
ic.proceed();
} catch (Exception ex) {
Logger.getLogger(SimpleInterceptor.class.getName()).log(Level.SEVERE, null, ex);
}
}
@PostActivate
public void onActivate(InvocationContext ic) {
try {
Logger.getLogger(SimpleInterceptor.class.getName()).info("activate " + this);
ic.proceed();
} catch (Exception ex) {
Logger.getLogger(SimpleInterceptor.class.getName()).log(Level.SEVERE, null, ex);
}
}
@PrePassivate
public void onPassivate(InvocationContext ic) {
try {
Logger.getLogger(SimpleInterceptor.class.getName()).info("passivate " + this);
ic.proceed();
} catch (Exception ex) {
Logger.getLogger(SimpleInterceptor.class.getName()).log(Level.SEVERE, null, ex);
}
}
@AroundInvoke
public Object aroundInvoke(InvocationContext ctx) throws Exception {
Logger.getLogger(SimpleInterceptor.class.getName()).info(ctx + " is invoked.");
return ctx.proceed();
}
@PreDestroy
public void onDestroy(InvocationContext ic) {
try {
Logger.getLogger(SimpleInterceptor.class.getName()).info("destroy " + this);
ic.proceed();
} catch (Exception ex) {
Logger.getLogger(SimpleInterceptor.class.getName()).log(Level.SEVERE, null, ex);
}
}
}

@Stateless(name="SimpleStatelessBean1")
public class SimpleStatelessBean1 implements SimpleStatelessLocal { ... }
@Stateless(name="SimpleStatelessBean2")
public class SimpleStatelessBean2 implements SimpleStatelessLocal { ... }
public class SimpleStatelessServlet extends HttpServlet {
@EJB(beanName="SimpleStatelessBean1")
private SimpleStatelessLocal simpleStatelessLocal1;
@EJB(beanName="SimpleStatelessBean2")
private SimpleStatelessLocal simpleStatelessLocal2;
...
}