Thread safety of the shared piece of memory - Java Memory Model

[r r]

Hello,

We have the simple pseudocode:

void main(String[] args) {

    MemoryBuffer b = new MemoryBuffer(); // it is a off-heap native piece of memory allocated by malloc via JNI

    b.init(); // it just write some data to the memory buffer by JNI

    startThreadsThatReadsFromBuffer(b); // this functions starts threads that read the b

    // There is no locks / synchronization etc.

}

It seems to be thread-safe in the sense of Java Memory Model. But, I cannot convince myself why it is correct. Especially, how can I be sure that worker threads see completely intizalized buffer b?

[Peter Veentjer]

There is a happens before edge between calling the start method of a thread and the thread running.

On JMM level that is sufficient. 

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[r r]

Thanks