MultiPolygon createMultiPolygon = fac.createMultiPolygon(polygons);
features[1].setDefaultGeometry(createMultiPolygon);
EditBlackboard bb = handler.getEditBlackboard();
PrimitiveShape shell = bb.newGeom(null, null).getShell();
handler.setCurrentShape(shell);
bb.addPoint(25,0, shell);
bb.addPoint(35,0, shell);
bb.addPoint(35,60, shell);
bb.addPoint(25,60, shell);
DifferenceFeatureCommand command=new DifferenceFeatureCommand(handler, EditState.NONE);