code: public boolean isNeighbor(String identifier, Geometry geometry) {
  		LineString lineString = getLineString(geometry);
  		if (lineString != null) {
  			int index = TransactionGeomIndexUtil.getIndex(identifier).getCoordinateIndex();
  			if (index >= 0 && coordinateIndex >= 0) {
  				if (coordinateIndex == 0) {
  					if (index == 1) {
  						return true;
  					}
  					if (lineString.isClosed() && index == lineString.getNumPoints() - 2) {
  						return true;
  					}
  				} else if (coordinateIndex == lineString.getNumPoints() - 2) {
  					if (index == coordinateIndex - 1) {
  						return true;
  					} else if (lineString.isClosed() && index == 0) {
  						return true;
  					}
  				} else {
  					if (index == coordinateIndex - 1 || index == coordinateIndex + 1) {
  						return true;
  					}
  				}
  			} else {
  				SC.warn("TransactionGeomIndex.isNeighbor: Implement me");
  			}
  		}
  		return false;
  	}
docs: Return true or false indicating of the given identifier for an edge or vertex is a neighbor for this index.
  
  @param identifier
  The given identifier to establish this status for. Must be a coordinate identifier.(TODO support edges
  as well)
  @param geometry
  A geometry that fits this index.
  @return Returns true or false.