Thanks, you're right on. That's what I'm after and that's exactly what Java needs to be useful for doing high performance computations in a sane fashion.
I switched to java from c in the mid 90's. I remember thinking how ridiculously wasteful it was to allocate an array on classes one at at time rather than as a block of memory. I think I was using berkeley DB at the time in c and it let you do that.
You have direct buffers but that's that...
You can use multiple arrays of primitives, inverting the problem 90%. None of the solutions is optimal, easy to maintain, etc.
Yes there is also the sun.misc.Unsafe class but of course that's skating on thin ice.
That ship has sailed.
What do you mean?
I think there was an opening for a fast safe alternative to C++ in HPC, but I think Rust has taken that spot now. Control over allocation, alignment and placement is important in HPC and imo Java took too long to address these issues.