Re: Re: define-simple-class and Java constructors

[Vladimir Tsichevski <wowa1 at online dot ru>]

Vladimir Tsichevski wrote:

>         Another question: how to execute methods on `super' in such
>         classes?
>
> The intention is that
>   (invoke (this <name-of-super-class>) 'method-name args ...)
> or something like it should work - but I very much doubt it does.
   It does not. You need special syntax to call methods as super. It
   has to compile to
   `invokespecial' (183) Java bytecode instead of `invokevirtual' (182).

   I've added to kawa (see attachement) a new built-in primitive syntax
   `primitive-super-method', so, for example,
   the following scheme declaration:

      ((primitive-super-method <javax.swing.tree.DefaultTreeCellRenderer>
                   "getTreeCellRendererComponent"
                   <java.awt.Component>
                   (
                    <javax.swing.JTree>
                    <object>
                    <boolean>
                    <boolean>
                    <boolean>
                    <int>
                    <boolean>))
       (this) tree value sel expanded leaf row hasFocus)

   now is equivalent to Jave code:

       super.getTreeCellRendererComponent(tree, value, sel, expanded, leaf,
                          row, hasFocus);

   To implement this I significally redesigned the
   kawa.standard.prim_method class. The main problem with that class
   was in that
   the 183 opcode required to call "as super" is used also in Java
   constructors and kawa  implicitly assumes
   that 183 opcode alwais means constructor, so I had to change all
   sentences like this

       if ( op_code == 183 ) // it must be constructor

   to more adequate

       if("<init>".equals(method.getName())

   Now I humbly ask you to check the code and add this or equivalent
   functionality to future kawa releases.
   I'm sure it would help many kawa users who need to use existing Java
   libraries.

   Regards,

   Vladimir Tsichevski

Attachment: kawa-call-super-patch.tar.gz
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