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NullPointerException while trying to access the entity's particular field

yuvaraj KumarAmudhan
Ranch Hand

Joined: Aug 22, 2009
Posts: 110
Hello all,

I have a table (BaseInfo) which has four fields called Id(primary key), Name, Age and Type. In this, "Type" field is Bigint datatype and it can hold 1 or 2 or null as value.
I have some another table (AdInfo) which refers the BaseInfo's Type field.

I inserted a record in BaseInfo table with the values (1, x, 28, (null)).

I can get the BaseInfo object by finding a record with the primary key "1" with the statement (em.find(BaseInfo.class, 1)).
And also i can print the values of that object except the "Type's value".

System.out.print(BaseInfoObj.getName()); --- Prints the value
System.out.print(BaseInfoObj.getAge()); ---- Prints the value

System.out.print(BaseInfoObj.getType()); ---- prints
javax.ejb.EJBException: java.lang.NullPointerException
ERROR [STDERR] at org.jboss.ejb3.tx.Ejb3TxPolicy.handleExceptionInOurTx(Ejb3TxPolicy.java:77)
ERROR [STDERR] at org.jboss.aspects.tx.TxPolicy.invokeInOurTx(TxPolicy.java:83)
ERROR [STDERR] at org.jboss.aspects.tx.TxInterceptor$Required.invoke(TxInterceptor.java:190)
ERROR [STDERR] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:102)
ERROR [STDERR] at org.jboss.aspects.tx.TxPropagationInterceptor.invoke(TxPropagationInterceptor.java:76)
ERROR [STDERR] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:102)
ERROR [STDERR] at org.jboss.ejb3.tx.NullInterceptor.invoke(NullInterceptor.java:42)
ERROR [STDERR] at org.jboss.aop.joinpoint.MethodInvocation.invokeNext(MethodInvocation.java:102)

Any idea regarding this?

Thank you!


yuvaraj KumarAmudhan
Ranch Hand

Joined: Aug 22, 2009
Posts: 110
Anybody having any idea about this?

This might be the basic thing but i don't know how to resolve this.
Palash Nandi
Ranch Hand

Joined: Jul 09, 2009
Posts: 34
Hi yuvaraj,
What kind of object is BaseInfoObj, does it have other references inside it, because as as shown by the previous statements its reference cannot be null. I think the method BaseInfoObj.getType() in internally calling some method of another internal reference object inside BaseInfoObj which is null.


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Jaikiran Pai
Marshal

Joined: Jul 20, 2005
Posts: 10240
    
168

And please post the entire exception stacktrace.

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yuvaraj KumarAmudhan
Ranch Hand

Joined: Aug 22, 2009
Posts: 110
Thanks for your replies. Just now i found the problem (Casting). Fixed.
 
It is sorta covered in the JavaRanch Style Guide.
 
subject: NullPointerException while trying to access the entity's particular field