Does initialized java array go onto stack or heap?

2020-03-13 08:56发布

问题:

void someMethod() {
  byte[] array = { 0, 0 };
}

Will this array be stored in heap or on the stack?

回答1:

You can think of it as always going on the heap.

I believe some smart VMs are able to stack-allocate objects if they can detect it's safe - but conceptually it's on the heap. In particular, all array types are reference types (even if the element type is primitive), so the array variable (which is on the stack) is just a reference to an object, and objects normally go on the heap.

In particular, imagine a small change:

byte[] someMethod() { 
    byte[] array = { 0, 0 };
    return array;
}

If the array were allocated on the stack, what would the returned reference have to refer to?



回答2:

It will be stored in the heap