EJB3 Null Pointer Exception

[Leandro Coutinho]

Hi my friends.

I'm studying EJB3 and using JBoss 7 for this. I created a @Remote bean.
But I'm getting NullPointerException when executing the code below. But it works if instead I put the exactly same code in a servlet (doGet for example).
So it's not initializing the placeOrder variable ... How can I fix this? Thank you!

public class PlaceOrderTestClient {
	
	@EJB
	private static PlaceOrder placeOrder;
	
	public static void main(String[] args) {
		placeOrder.setBidderID(100l);
                // ...
		System.out.println("Order confirmation number: " + orderID);
	}

}

[Jaikiran Pai]

Injection in normal Java clients isn't supported by the spec. You could inject in Java EE "application clients", but that support isn't available in the current AS7 releases.

[Lucas Smith]

Use JNDI lookup instead of DI if you are accessing the bean from within external client.

[Leandro Coutinho]

Thanks Jaikiran and Lucas.

So I need to do something like this:

Hashtable<String, String> env = new Hashtable<String, String>();
		env.put(Context.INITIAL_CONTEXT_FACTORY, "org.jnp.interfaces.NamingContextFactory");
		env.put(Context.URL_PKG_PREFIXES, "org.jboss.naming:org.jnp.interfaces");
		env.put(Context.PROVIDER_URL, "jnp://localhost:1099");
		Context ic = new InitialContext(env);
		Object obj = ic.lookup(PlaceOrder.class.getName());
		System.out.println("lookup returned: " + obj);
		
		placeOrder = (PlaceOrder) obj;

Exception in thread "main" javax.naming.NoInitialContextException: I get this: Cannot instantiate class: org.jnp.interfaces.NamingContextFactory [Root exception is java.lang.ClassNotFoundException: org.jnp.interfaces.NamingContextFactory]
It seems that I need to start JBoss with the -b option. But I'm using Eclipse and I don't know to this in Eclipse.

[Lucas Smith]

Maybe you have to add some .jars to the classpath of your client, especially when you use the client outside the container,
For example while using Glassfish there must be gf-client.jar.

[Leandro Coutinho]

Lucas Smith wrote:Maybe you have to add some .jars to the classpath of your client, especially when you use the client outside the container,
For example while using Glassfish there must be gf-client.jar.

ok. I'm using JBoss AS 7. I download this jbossall-client.jar from here: http://www.java2s.com/Code/Jar/JKL/Downloadjbossallclientjar.htm
Now I'm getting the exception below. How do I know which port to choose?

Exception in thread "main" javax.naming.CommunicationException: Could not obtain connection to any of these urls: localhost:9999 and discovery failed with error: javax.naming.CommunicationException: Receive timed out [Root exception is java.net.SocketTimeoutException: Receive timed out] [Root exception is javax.naming.CommunicationException: Failed to retrieve stub from server localhost:9999 [Root exception is java.io.StreamCorruptedException: invalid stream header: 00000018]]
	at org.jnp.interfaces.NamingContext.checkRef(NamingContext.java:1452)
	at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:597)
	at org.jnp.interfaces.NamingContext.lookup(NamingContext.java:590)
	at javax.naming.InitialContext.lookup(InitialContext.java:409)
	at ejb3inaction.buslogic.PlaceOrderTestClient2.main(PlaceOrderTestClient2.java:23)
Caused by: javax.naming.CommunicationException: Failed to retrieve stub from server localhost:9999 [Root exception is java.io.StreamCorruptedException: invalid stream header: 00000018]
	at org.jnp.interfaces.NamingContext.getServer(NamingContext.java:266)
	at org.jnp.interfaces.NamingContext.checkRef(NamingContext.java:1423)
	... 4 more
Caused by: java.io.StreamCorruptedException: invalid stream header: 00000018
	at java.io.ObjectInputStream.readStreamHeader(ObjectInputStream.java:800)
	at java.io.ObjectInputStream.<init>(ObjectInputStream.java:297)
	at org.jnp.interfaces.NamingContext.getServer(NamingContext.java:253)
	... 5 more