Subj : Re: Problem using JS Objects and JS Objects implementing Java Interfaces
To   : Alvaro Diaz <alvaro.diaz@roxes.com>
From : Igor Bukanov <igor@fastmail.fm>
Date : Wed Apr 30 2003 04:33 pm

alvaro.diaz@roxes.com wrote:
 > ...
 > i have found a working solution for my problem:
 >
 > function Directory( path)
 > {
 >         this.filenameFilter = new java.io.FilenameFilter()
 >         {
 >                 directories:[],
 >                 files:[],
 >
 >                 accept:function( dir, name)
 >                 {
 >                         if( new java.io.File( dir, name).isDirectory())
 >                                 this.directories.push( [name, new
 > Directory( path + "/" + name)]);
 >                         else
 >                                 this.files.push( name);
 >                 }
 >         }
 >
 >         new java.io.File( path).list( this.filenameFilter);
 >
 >         this.directories = this.filenameFilter.delegee.directories;
 >         this.directories.sort();
 >         this.files = this.filenameFilter.delegee.files;
 >         this.files.sort();
 >
 >         delete this.filenameFilter;
 > }
 >
 > var root = new Directory( ".");
 >
 > but its an ugly one. do you know an more elegant solution ?
 > especially copying from the delegee's seems to me really bad.
 >
 > my hardest problem is probably the scoping.
 >
 > if you know how to code it better please send it to me.

This is due to a very bad JS design where nested functions will have as 
their this this original scope object, not this for parent function that 
calls them.

A simple workaround would be to add something like var new_object = this 
to Directory and use it instead of this everywhere:

function Directory( path)
{
	var new_object = this;
	
	new_object.directories = [];
         new_object.files = [];
	
	var filenameFilter = new java.io.FilenameFilter()
         {
                 accept:function( dir, name)
                 {
                         if( new java.io.File( dir, name).isDirectory())
                                 new_object.directories.push( [name, new
Directory( path + "/" + name)]);
                         else
                                 new_object.files.push( name);
                 }
         }

         new java.io.File( path).list( filenameFilter);

         new_object.directories.sort();
         new_object.files.sort();
}

var root = new Directory( ".");


Regards, Igor

.