what happen with my entity bean ,need expert help

[ejbiva]

I just a new learner for EJB3.0.I download the jboss-EJB-3.0_Preview_2 for testing ,and the session bean is ok,but when I run the entity bean ,the fatal error occurs .That seems like lots of mess .My environment is Jboss4.2.0GA. The exception just as follow.


[java] Exception in thread "main" javax.ejb.EJBException:
java.lang.NullPoi
nterException
[java] at org.jboss.ejb3.tx.Ejb3TxPolicy.handleExceptionInOurTx(Ejb3TxP
olicy.java:63)
[java] at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:83)

[java] at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxIntercep
tor.java:191)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropag
ationInterceptor.java:76)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.stateful.StatefulInstanceInterceptor.invoke(St
atefulInstanceInterceptor.java:83)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.security.AuthenticationInterceptor.invoke(A
uthenticationInterceptor.java:77)
[java] at org.jboss.ejb3.security.Ejb3AuthenticationInterceptor.invoke(
Ejb3AuthenticationInterceptor.java:106)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagatio
nInterceptor.java:46)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(As
ynchronousInterceptor.java:106)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.stateful.StatefulContainer.dynamicInvoke(State
fulContainer.java:333)
[java] at org.jboss.aop.Dispatcher.invoke(Dispatcher.java:106)
[java] at org.jboss.aspects.remoting.AOPRemotingInvocationHandler.invok
e(AOPRemotingInvocationHandler.java:82)
[java] at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:73
4)
[java] at org.jboss.remoting.transport.socket.ServerThread.processInvoc
ation(ServerThread.java:560)
[java] at org.jboss.remoting.transport.socket.ServerThread.dorun(Server
Thread.java:369)
[java] at org.jboss.remoting.transport.socket.ServerThread.run(ServerTh
read.java:165)
[java] at org.jboss.remoting.MicroRemoteClientInvoker.invoke(MicroRemot
eClientInvoker.java:163)
[java] at org.jboss.remoting.Client.invoke(Client.java:1550)
[java] at org.jboss.remoting.Client.invoke(Client.java:530)
[java] at org.jboss.aspects.remoting.InvokeRemoteInterceptor.invoke(Inv
okeRemoteInterceptor.java:62)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.tx.ClientTxPropagationInterceptor.invoke(Cl
ientTxPropagationInterceptor.java:61)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.security.SecurityClientInterceptor.invoke(S
ecurityClientInterceptor.java:53)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.remoting.IsLocalInterceptor.invoke(IsLocalInte
rceptor.java:72)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.stateful.StatefulRemoteProxy.invoke(StatefulRe
moteProxy.java:135)
[java] at $Proxy1.checkout(Unknown Source)
[java] at org.jboss.tutorial.entity.client.Client.main(Client.java:44)
[java] at org.jboss.aspects.remoting.InvokeRemoteInterceptor.invoke(Inv
okeRemoteInterceptor.java:74)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.tx.ClientTxPropagationInterceptor.invoke(Cl
ientTxPropagationInterceptor.java:61)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.security.SecurityClientInterceptor.invoke(S
ecurityClientInterceptor.java:53)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.remoting.IsLocalInterceptor.invoke(IsLocalInte
rceptor.java:72)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.stateful.StatefulRemoteProxy.invoke(StatefulRe
moteProxy.java:135)
[java] at $Proxy1.checkout(Unknown Source)
[java] at org.jboss.tutorial.entity.client.Client.main(Client.java:44)
[java] Caused by: java.lang.NullPointerException
[java] at org.jboss.tutorial.entity.bean.ShoppingCartBean.checkout(Shop
pingCartBean.java:36)
[java] at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
[java] at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAcces
sorImpl.java:39)
[java] at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMet
hodAccessorImpl.java:25)
[java] at java.lang.reflect.Method.invoke(Method.java:585)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:112)
[java] at org.jboss.ejb3.interceptor.InvocationContextImpl.proceed(Invo
cationContextImpl.java:166)
[java] at org.jboss.ejb3.interceptor.EJB3InterceptorsInterceptor.invoke
(EJB3InterceptorsInterceptor.java:63)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.entity.ExtendedPersistenceContextPropagationIn
terceptor.invoke(ExtendedPersistenceContextPropagationInterceptor.java:57)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.entity.TransactionScopedEntityManagerIntercept
or.invoke(TransactionScopedEntityManagerInterceptor.java:54)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.AllowedOperationsInterceptor.invoke(AllowedOpe
rationsInterceptor.java:47)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:79)

[java] at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxIntercep
tor.java:191)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropag
ationInterceptor.java:76)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.stateful.StatefulInstanceInterceptor.invoke(St
atefulInstanceInterceptor.java:83)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.aspects.security.AuthenticationInterceptor.invoke(A
uthenticationInterceptor.java:77)
[java] at org.jboss.ejb3.security.Ejb3AuthenticationInterceptor.invoke(
Ejb3AuthenticationInterceptor.java:106)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.ENCPropagationInterceptor.invoke(ENCPropagatio
nInterceptor.java:46)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.asynchronous.AsynchronousInterceptor.invoke(As
ynchronousInterceptor.java:106)
[java] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInv
ocation.java:101)
[java] at org.jboss.ejb3.stateful.StatefulContainer.dynamicInvoke(State
fulContainer.java:333)
[java] at org.jboss.aop.Dispatcher.invoke(Dispatcher.java:106)
[java] at org.jboss.aspects.remoting.AOPRemotingInvocationHandler.invok
e(AOPRemotingInvocationHandler.java:82)
[java] at org.jboss.remoting.ServerInvoker.invoke(ServerInvoker.java:73
4)
[java] at org.jboss.remoting.transport.socket.ServerThread.processInvoc
ation(ServerThread.java:560)
[java] at org.jboss.remoting.transport.socket.ServerThread.dorun(Server
Thread.java:369)
[java] at org.jboss.remoting.transport.socket.ServerThread.run(ServerTh
read.java:165)
[java] Java Result: 1

[wolfc]

Use AS 4.2.1 GA

[ejbiva]

Dear wolfc ,why use AS 4.2.1 GA? any defect with AS 4.2.0?I am sorry one thing I should mentioned,that is I have never create related table in the oracle.because the ejb should create it indtead of me,that is true?

[wolfc]

Don't install any of the preview release into AS 4.2. Use 4.2.1 as installed, by default it has the latest EJB 3 installation.

[ejbiva]

wolfc,I tried it again.but is same. sessionBean is initiated succeesfuly,but the accessing to entity bean failed.why?The Exception is same

[alrubinger]

Could you post your code for the Session Bean?

S,
ALR

[ejbiva]

hi ALRubinger,the SessionBean just as follows
@Stateful
public class ShoppingCartBean implements ShoppingCart
{
@Inject
private EntityManager manager;
private Order order;

public void buy(String product, int quantity, double price)
{
if (order == null) order = new Order();
order.addPurchase(product, quantity, price);
}

public Order getOrder()
{
return order;
}


public void checkout()
{
manager.create(order);
}
}
/// Entity bean
@Entity
@Table(name = "PURCHASE_ORDER")
public class Order implements java.io.Serializable
{
private int id;
private double total;
private Collection lineItems;

@Id(generate = GeneratorType.AUTO)
public int getId()
{
return id;
}

public void setId(int id)
{
this.id = id;
}

public double getTotal()
{
return total;
}

public void setTotal(double total)
{
this.total = total;
}

public void addPurchase(String product, int quantity, double price)
{
if (lineItems == null) lineItems = new ArrayList();
LineItem item = new LineItem();
item.setOrder(this);
item.setProduct(product);
item.setQuantity(quantity);
item.setSubtotal(quantity * price);
lineItems.add(item);
total += quantity * price;
}

@OneToMany(cascade = CascadeType.ALL, fetch = FetchType.EAGER)
@JoinColumn(name = "order_id")
public Collection getLineItems()
{
return lineItems;
}

public void setLineItems(Collection lineItems)
{
this.lineItems = lineItems;
}
}

@Entity
@Table(name = "order_line_item")
public class LineItem implements java.io.Serializable
{
private int id;
private double subtotal;
private int quantity;
private String product;
private Order order;


@Id(generate = GeneratorType.AUTO)
public int getId()
{
return id;
}

public void setId(int id)
{
this.id = id;
}

public double getSubtotal()
{
return subtotal;
}

public void setSubtotal(double subtotal)
{
this.subtotal = subtotal;
}

public int getQuantity()
{
return quantity;
}

public void setQuantity(int quantity)
{
this.quantity = quantity;
}

public String getProduct()
{
return product;
}

public void setProduct(String product)
{
this.product = product;
}

@ManyToOne
@JoinColumn(name = "order_id")
public Order getOrder()
{
return order;
}

public void setOrder(Order order)
{
this.order = order;
}
}
/////// and testing console as follows
public class Client
{
public static void main(String[] args) throws Exception
{
InitialContext ctx = new InitialContext();
// ShoppingCart cart = (ShoppingCart) ctx.lookup(ShoppingCart.class.getName());
//Calculator calculator = (Calculator) ctx.lookup("CalculatorBean/remote");
ShoppingCart cart = (ShoppingCart) ctx.lookup("ShoppingCartBean/remote");
System.out.println("Buying 2 memory sticks");
cart.buy("Memory stick", 2, 500.00);
System.out.println("Buying a laptop");
cart.buy("Laptop", 1, 2000.00);

System.out.println("Print cart:");
Order order = cart.getOrder();
System.out.println("Total: $" + order.getTotal());
for (LineItem item : order.getLineItems())
{
System.out.println(item.getQuantity() + " " + item.getProduct() + " " + item.getSubtotal());
}

System.out.println("Checkout");
cart.checkout();

}
}

any defect?

[waynebaylor]

instead of

@Inject
private EntityManager manager;

you should try

@PersistenceContext(unitName="persistence_unit_name")
EntityManager manager;

[alrubinger]

Agree w/ Wayne. Beat me to it. :)

[ejbiva]

ok I will try it ,any way ,Thank you for all ,two gentlemen,:) ,I am from china.nice meet you

[jfheintz]

Hello everybody,

I have exactly the same problem. I used to work with Jboss AS 4.2.0.GA. I ahve migrate to Jboss AS 4.2.1.GA with no difference.

Have you resolved this?


Thanks

JF HEINTZ

[alrubinger]

JF HEINTZ -

Are you also using @Inject instead of @PersistenceUnit? Post your code?

ejbiva, Did this work for you?

S,
ALR

[jfheintz]

No I have followed your instruction, here is my code:

MySite.java:

package test;

@javax.persistence.Entity
@javax.persistence.Table(name="SI_SITE")
public class MySite {

@javax.persistence.Column(name="siteId")
@javax.persistence.Id
private java.lang.Long siteId;

@javax.persistence.Column(name="name")
private java.lang.String name;
@javax.persistence.Column(name="description")
private java.lang.String description;
@javax.persistence.Column(name="staticSite")
private boolean staticSite;
@javax.persistence.Column(name="status")
private int status;

public MySite() {
}

... getter and setter for the previous attributes

}


The client (part of a session bean):

EjbLocator ejbLocator=EjbLocator.getLocator();
MySite siteEJB3=ejbLocator.find(MySite.class, new Long(1));

EjbLocator.java:

public class EjbLocator {

@PersistenceContext(unitName="StatInfoUnit")
private EntityManager manager;

private static Context ctx;

private static EjbLocator instance = new EjbLocator();

private EjbLocator() {
try {
ctx = new InitialContext();
} catch (NamingException e) {
logger.error(e.getMessage());
}
}

public static EjbLocator getLocator() {
return instance;
}

private T getEjb(Class ejbClass, String name) {
try {
T service = (T) new InitialContext().lookup("Statinfo/" + name
+ "/local");
return service;
} catch (NamingException e) {
return null;
}
}


public T find(Class ejb3Class, Object id) {
return manager.find(ejb3Class, id);
}

public void persist(Object ejb3Object) {
manager.persist(ejb3Object);
}

}

I have a persistence.xml in META-INF dir:


<persistence-unit name="StatInfoUnit">
<jta-data-source>java:/StatInfoDS</jta-data-source>
<!-- Explicitly define mapping file path, else Hibernate won't find the default -->
<mapping-file>META-INF/orm.xml</mapping-file>
test.MySite
<!-- exclude-unlisted-classes=true: Prevent annotation scanning. In this app we are purely driven by orm.xml -->
<exclude-unlisted-classes>false</exclude-unlisted-classes>
org.hibernate.ejb.HibernatePersistence




</persistence-unit>


I have a orm.xml in META-INF dir:
<?xml version="1.0" encoding="UTF-8"?>
<entity-mappings
xmlns="http://java.sun.com/xml/ns/persistence/orm"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm orm_1_0.xsd"
version="1.0">
<persistence-unit-metadata>
</persistence-unit-metadata>
</entity-mappings>

Deployment is OK but the exception (Nullpointer) occurs when the client part is called, any idea?

Thanks a lot for your help,

JF

[jfheintz]

I reintroduce persistence.xml:


<persistence-unit name="StatInfoUnit">
<jta-data-source>java:/StatInfoDS</jta-data-source>
<mapping-file>META-INF/orm.xml</mapping-file>
<*class>test.MySite</*class>
<exclude-unlisted-classes>false</exclude-unlisted-classes>
<*provider>org.hibernate.ejb.HibernatePersistence</*provider>
<*properties>
<*property name="hibernate.hbm2ddl.auto" value="update" />
<*property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
</*properties>
</persistence-unit>


Note: remove the * (it just for the display in the forum)
Note: If I don't specify the class tag "test.MySite" the log does not show the EJB mapping with the DB

[alrubinger]

Can you please post the stack trace you're getting?

S,
ALR