Memory Allocation

[Chris Sommers]

Estmeemed wizards,
How can I estimate how much memory an object or bunch of
objects consume - besides indirectly, e.g. looking at
Runtime.getRuntime().totalMemory()? For example, how big is
a Vector containing 10,000 of class Double? I'm sure it will
be JVM/platform-dependent, but there must be a way to
estimate it.

Is there documentation on this topic? It seems fundamental.

-chris