Jigsaw Quick Start guide

[Alex Buckley]

I recall discussion of different entrypoints when a module is used in 
different contexts, e.g. applet v. command-line launcher.

However, the Java Module System requirements don't say anything about 
this, so I stuck with a solitary, unqualified 'class ...' construct in 
the module declaration. The closest "context-aware" requirement is that 
a module "can be used both as a JAR on the class path and installed as a 
module in a module library".

Alex

On 6/28/2011 10:41 AM, Roger Riggs wrote:
> Hi,
> 
> Thanks for the writeup of jigsaw modules.
> 
> This is  more of a comment on the module compilation unit grammar
> and the choice of keywords and semantics.
>   http://openjdk.java.net/projects/jigsaw/doc/topics/grammar.html
> 
> The "class" keyword in the module-info.java sticks out as an awkward usage.
> There are plenty of classes in the module.  The significance the class
> is that it is a/the main class.  The keyword should identify the usage 
> of the class.
> "main" would be more meaningful and intuitive.
> 
> The "class" keyword is being overloaded. While it identifies a main 
> class it is
> also being used to indicate module is the root of the static context for
> the module as a whole and the class name is not relevant to that function.
> 
> A separate keyword defining the module as requiring a static context
> would clearer to separate the semantics of the entry point from the 
> "classloader"
> behavior.
> 
> Can a module, like a jar file could contain multiple classes with main 
> methods?
> In current usage, for jar files, the main class can be given on the 
> command line
> allowing multiple applications to share the overhead of packaging.
> Having a solitary entry point may result in extra overhead because each 
> application
> must be in a separate module.
> 
> Roger