Replacing Unsafe.allocateInstance

[Paul Sandoz]

On 2 Aug 2015, at 09:52, Christoph Engelbert <chris at hazelcast.com> wrote:

> Hey Paul,
> 
> The assumption of non creating JDK classes without calling constructors is not completely right.
> Seen serialization frameworks that create String instances and “injecting” a char[] afterwards however I prefer calling the package private constructor to just prevent copying of the char[] (in cases where it won’t break the immutability contract like deserialisation)

This is of course playing with fire on many levels and totally unsupported :-)

The package private constructor could go away, the internals of String could change (e.g. optimise for UTF-8 ) in a manner that is also not global (imagine species of String, each with different layouts, char[], byte[] UTF-8, String object header fused with an array).

We need frozen arrays:

  http://cr.openjdk.java.net/~jrose/arrays/frozen-array-value-rules.html

Paul.