public void addPriorityPackage(String pkg){
  if (_priorityPackages == null)   _priorityPackages=new String[0];
  int oldLength=_priorityPackages.length;
  String[] newPkgs=new String[oldLength + 1];
  System.arraycopy(_priorityPackages,0,newPkgs,0,oldLength);
  if (!pkg.endsWith("."))   pkg=pkg + '.';
  newPkgs[oldLength]=pkg;
  _priorityPackages=newPkgs;
}

public void addPriorityPackage ( String pkg ) { if ( _priorityPackages == null ) _priorityPackages = new String [ 0 ] ; int oldLength = _priorityPackages . length ; String [ ] newPkgs = new String [ oldLength + 1 ] ; System . arraycopy ( _priorityPackages , 0 , newPkgs , 0 , oldLength ) ; if ( ! pkg . endsWith ( "." ) ) pkg = pkg + '.' ; newPkgs [ oldLength ] = pkg ; _priorityPackages = newPkgs ; }
add to the list of packages that take priority over the parent
