Re: [9fans] Re: Threads: Sewing badges of honor onto a Kernel

[David Tolpin <dvd@davidashen.net>]

> in other words: if you're capable of understanding `finalised virtual hyperstationary factory class',
> remembering the Java class hierarchy, and all the details of the Java Media Framework,

In fact, there is no such thing as 'virtual' in Java, it is from other
languages. Finalised cannot be a feature of a class in a hierarchy,
since finalized is a state of an object after it was deleted and it
is only needed to define the semantics of the language, not to
program in it; remembering all the details
of Java Media Framework is no more necessary than remembering all
the details of PDF 1.5 specification -- unless you earn money by
winning contests on writing multimedia java applets or
checking PDF generators for conformance.

Factory in Java is a simple concept, one more level of indirection.
Think of it as something similar to 'bind' in Plan9.

In general, Java is very close to Plan9 in many things. It is built
to provide a cleaner and smaller alternative to C++; it offers very
few concepts to learn -- and the extensive libraries are not meant
to learn -- there are javadocs for them. The core language and system
design is small and logical. It bears many ideas from Oberon (the system
acme took its interface and interaction design), including
the language design and the idea of embedded applets.

Parallel programming in Java is easy and natural, as easy and natural
as in other language or system or even easier, dare I say it.  You
just use threads, and use basic language features, such as variable
scopes, to have shared and private thread resources. No additional
flags and bits to remember; everything is easy and straightforward.

I think that the major objection against Java is its closedness,
but Plan9 has this problem too -- and it is being solved for both
designs.

David Tolpin