code: private boolean getPresenceOfNitro(IAtomContainer ac, IAtom atom) {
          List neighbours = ac.getConnectedAtomsList(atom);
          List second = null;
          IBond bond = null;
          //int counter = 0;
          for (int i = 0; i < neighbours.size(); i++) {
              IAtom neighbour = (IAtom) neighbours.get(i);
              if (neighbour.getSymbol().equals("N")) {
                  second = ac.getConnectedAtomsList(neighbour);
                  for (int b = 0; b < second.size(); b++) {
                      IAtom conAtom = (IAtom) second.get(b);
                      if (conAtom.getSymbol().equals("O")) {
                          bond = ac.getBond(neighbour, conAtom);
                          if (bond.getOrder() == IBond.Order.DOUBLE) {
                              return true;
                          }
                      }
                  }
              }
          }
          return false;
      }
docs: Gets the presenceOfN=O attribute of the XLogPDescriptor object.
  
  @param  ac    Description of the Parameter
  @param  atom  Description of the Parameter
  @return       The presenceOfNitor [boolean]