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Jon Camilleri
Ranch Hand

Joined: Apr 25, 2008
Posts: 664

"One of the notable features of Java generics is the erasure of generic types in the virtual
machine. Perhaps surprisingly, the erased classes still retain some faint memory of their
generic origin
Core Java Vol I (8th Ed) P. 641

Somehow this reminds me of weak references, is this correct?
Can we read this information somehow?

Related links?
1. Weak references
2. Understanding weak references

Jesper de Jong
Java Cowboy
Saloon Keeper

Joined: Aug 16, 2005
Posts: 15092

No, this does not at all have anything to do with weak references.

Is there some more context in the book? (I don't have the book so I can't look it up).

Java Beginners FAQ - JavaRanch SCJP FAQ - The Java Tutorial - Java SE 8 API documentation
Stephan van Hulst

Joined: Sep 20, 2010
Posts: 4627

I assume it has to do with the fact that when you compile the code, the bytecode still knows that it is generic, so if you write new code that interacts with this compiled class, it will be able to perform type safety checks, as opposed to compiled code that used raw types. All the erasure actually takes place right before run time. This is when all generic information is discarded.

The mind is a strange and wonderful thing. I'm not sure that it will ever be able to figure itself out, everything else, maybe. From the atom to the universe, everything, except itself.
I agree. Here's the link:
subject: Generics
It's not a secret anymore!