public ExternalFolder(IProject project,IContainer parent,File file){
  super(new Path(file.getAbsolutePath()),null);
  this.file=file;
  this.project=project;
  this.parent=parent;
}

public ExternalFolder ( IProject project , IContainer parent , File file ) { super ( new Path ( file . getAbsolutePath ( ) ) , null ) ; this . file = file ; this . project = project ; this . parent = parent ; }
creates a new external folder with the given project , parent and the external resource that the new instance wraps .
