Is this a java weakness ?!!

Hello, I'm a french student and i'm a java developer;
I have not a good english i hope that you will understand me !
A friend tell me that in java when the secret keys are being used they are in memory and could, in theory, be accessed by another application running at the same time.
In C it's possible to take steps against such theft, but in Java the programmer has almost no control of the memory, and keys held in RAM could conceivably be read by another application. Even worse, if the encryption program is relying on Java garbage collection, there's no telling how long those keys will actually exist in memory; they could even find themselves paged into virtual memory (on the hard drive) where they might hang about for months before that part of the hard drive is used again!
Is it true ? I'm developing a cryptographic project in java and I am afraid of to commit a huge error (choosing java)!!
please help me !!
you can contact me directly at [email protected]

FYI : This question would've been better directed to the Security -> Cryptography section.
Anything in RAM could potentially be read by another program, this it not restricted to Java.
Good design practises will help minimise exposing private keys to other Java classes though.
Eg.
- make the key private and transient ( not serialised to disc ).
- do not implement serializable
- Make any accessor methods final, so they can't be overridden by another
class which attempts to extend it.
- Define explicit "cleanup" methods, to wipe your data, avoiding your reliance
on the garbage collector.
regards,
Owen

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