Re: [igraph] Is it possible to use igraph in Java?

[Tamas Nepusz]

Hi Laurence,

> A possible way to (ab)use igraph in Java would be SWIG (Simplified  
> Wrapper and Interface Generator). SWIG connects programs written in  
> c/c++ with many high-level programming and scripting languages. It  
> should be able to wrap all igraph functions and structures.
I took a quick look at SWIG - it looks quite sophisticated, but I'm  
worried about a few things. First, it looks like it maps C functions  
to static methods inside a special "module" class in Java, which means  
that all igraph_* functions would become static methods of the  
generated igraph module instead of instance methods of a generated  
Graph class. I don't know if there's a way to tell SWIG to map  
specific functions to instance methods of a given class instead.
Second, every igraph function returns an error code and the actual  
result is returned as an output argument instead. (There might even be  
multiple output arguments for the same function; i.e.,  
igraph_isomorphic_vf2 can return a yes/no answer and a mapping between  
the vertices of the two graphs if they are isomorphic). I'm not sure  
how to handle this in Java. Obviously, igraph error codes should be  
converted to exceptions and if there is only one output argument for a  
function, then that single argument should be returned in Java as a  
return value, but can SWIG do that automatically? If anyone in the  
list has ever used SWIG before, I'd be interested to hear your  
thoughts about that.

--
Tamas