code: public static void geometryOffSetCurve(ArrayList<LineString> list, Geometry geometry, double offset, BufferParameters bufferParameters) {
          final List curves = new OffsetCurveSetBuilder(geometry, offset, new OffsetCurveBuilder(geometry.getFactory().getPrecisionModel(), bufferParameters)).getCurves();
          final Iterator<SegmentString> iterator = curves.iterator();
          while (iterator.hasNext()) {
              list.add(geometry.getFactory().createLineString(iterator.next().getCoordinates()));
          }
      }
docs: Compute the offset curve for a polygon, a point or a collection of geometries
  @param list
  @param geometry
  @param offset
  @param bufferParameters