code: public void onGeometryEditStart(GeometryEditStartEvent event) {
  		String geometryType = service.getGeometry().getGeometryType();
  		if (Geometry.LINEAR_RING.equals(geometryType) || Geometry.POLYGON.equals(geometryType)
  				|| Geometry.MULTI_POLYGON.equals(geometryType)) {
  			setDisabled(false);
  		}
  	}
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