There's a combo of things in Java that combine to make this hard to do unfortunately. There's no concept of reference ownership at all (Because GC makes it unn

There's a combo of things in Java that combine to make this hard to do unfortunately. There's no concept of reference ownership at all (Because GC makes it unnecessary). Meaning, the syntax doesn't enforce (and in some ways encourages) you to pass and store your references anywhere you want, giving them any lifetime you want. The issue with this is that if you want to insert your own deallocate call, you have to guarantee that every place the reference is passed to never attempts to store this reference. This includes already compiled code, so it already becomes basically impossible to use this optimization when you use any std library functions. When it's not compiled code, then the compiler still has to attempt to do static-analysis on the source code to attempt to figure out if it's going to store this reference somewhere or not. If the static-analysis fails to be conclusive then you have to give-up.