java - What exactly happens in memory when we allocate an array using an empty curly braces? -

Both of the following examples come back to 0, if we say length :

  int [] [] B = {};  

or

  int [] a = {};  

I think the two objects in general are allocated on the heap: I think in the second case, one object (empty table) type int [] is allocated, but in the first case?

What is happening under the hood under these circumstances?