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Generic + Reflection - Why following code fails ?

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Hi all,
Can any body make this code running ? And please do explain me what is happening i.e. why it is failing ?

Above code fires following exception:

I think it is due to returnType reference which is not of generic type.

Any help will be appreciated.

- Pranav
Java Cowboy
Posts: 16084
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I just tried this out with JDK 6 and I get:

Exception in thread "main" java.lang.ClassCastException: sun.reflect.generics.reflectiveObjects.ParameterizedTypeImpl cannot be cast to java.lang.Class
at TestMain.main(TestMain.java:19)

Note that the exception happens in line 19, which is this line:

Class returnClass = (Class) returnType;

Note that getGenericReturnType() returns a Type object, which is not necessarily a Class. In fact, if the return type is a generic type, it's not a Class but a ParameterizedType.

Here's an enhanced version of your code.

[ February 16, 2007: Message edited by: Jesper Young ]
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