instanceof not working with aspects in Spring

Asked Jun 13 '16 at 14:09

Active Jun 13 '16 at 14:24

Viewed 825 times

I have a Spring Bean obtained from a factory, say,

private ObjectFactory<GoodStudent> studentFactory;

public void somemethod() {
    IStudent astudent = studentFactory.getObject();
    System.out.println(astudent instanceof GoodStudent); // prints false.
}

Does this happen because of Aspects? Because, I have a method in GoodStudent that is augmented using Aspects(around aspect), like,

public class GoodStudent implements IStudent { ...
    @UsesAspect
    public void logStudent() {....}

Is this a limitation in Spring or am I missing something?

Note : System.out.println(astudent instanceof IStudent); // prints true

edited Jun 13 '16 at 14:24

zapl

63,179
10
123
154

asked Jun 13 '16 at 14:09

Antho Christen

1,369
1
10
21

Does `GoodStudent` implement `IStudent`? – Mapsy Jun 13 '16 at 14:13
@Alex T. yes, it does. logStudent is in-fact a overridden method. – Antho Christen Jun 13 '16 at 14:14
Ah okay. From the source you've provided all we see is `public class GoodStudent {` which would imply that it doesn't. – Mapsy Jun 13 '16 at 14:17
Can we see the implementation of `ObjectFactory.getObject()` when returning a type of `IStudent`? – Mapsy Jun 13 '16 at 14:18
it's a spring Interface method. **org.springframework.beans.factory.ObjectFactory** – Antho Christen Jun 13 '16 at 14:24
What does `System.out.println(astudent.getClass())` print? An `ObjectFactory` should only produce objects instanceof `Foo`. – zapl Jun 13 '16 at 14:25
Could you show us your spring set-up, please? – Michal Jun 13 '16 at 14:35
@zapl - prints com.sun.proxy.$85 !! – Antho Christen Jun 13 '16 at 14:37
@Michal - I've used javax annotations mostly..the beans file just has `aop:aspectj-autoproxy` and `` – Antho Christen Jun 13 '16 at 14:43
1

means you have a "jdk dynamic proxy" per http://docs.spring.io/spring/docs/current/spring-framework-reference/html/aop.html#aop-introduction-proxies which only works with interfaces, you'll need to configure that is uses CGLib proxies (or properly "program to the interface" and stay with `IStudent` only) – zapl Jun 13 '16 at 14:45
How do you retrieve the private ObjectFactory studentFactory; ? – Michal Jun 13 '16 at 14:45
The annotations count as spring set-up too! :) – Michal Jun 13 '16 at 14:47
@zapl, the reason its getting casted back is cause I'm invoking `astudent.equals(Object anthoerStudent)` where another is also got from the **ObjectFactory**. – Antho Christen Jun 13 '16 at 14:51
@Michal `ObjectFactory studentFactory;` is Autowired... – Antho Christen Jun 13 '16 at 14:54
1

@zapl thanks for the heads up..It works now..forced it to use CGLIB instead of JDK dynamic proxy per the Spring docs. – Antho Christen Jun 13 '16 at 15:06

instanceof not working with aspects in Spring

0 Answers0