@JsonIgnore
  public PolymerNotation getPolymerNotation(String id) {
    for (PolymerNotation polymer : listOfPolymers) {
      if (polymer.getPolymerID().getId().equals(id)) {
        return polymer;
      }
    }

    return null;
  }
@JsonIgnore
  public PolymerNotation getPolymerNotation(String id) {
    for (PolymerNotation polymer : listOfPolymers) {
      if (polymer.getPolymerID().getId().equals(id)) {
        return polymer;
      }
    }

    return null;
  }
@ JsonIgnore public PolymerNotation getPolymerNotation ( String id ) { for ( PolymerNotation polymer : listOfPolymers ) { if ( polymer . getPolymerID ( ) . getId ( ) . equals ( id ) ) { return polymer ; } } return null ; }
method to get a specific polymer by its id

@param id polymer id
@return polymer
method to get a specific polymer by its id