Cell Neighbor List: Java Code

public class Space2DCell.AtomIterator.UpNeighbor implements Atom.Iterator

//Returns next atom from iterator

public Atom next() {

nextAtom = (Atom)coordinate.parent(); //atom to be returned

coordinate = coordinate.nextNeighbor; //prepare for next atom

if(coordinate == null) {advanceCell();} //cell is empty; get atom from next cell

return nextAtom;

}

//Advances up through list of cells until an occupied one is found

private void advanceCell() {

while(coordinate == null) { //loop while on an empty cell

cell = cell.nextSite(); //next cell

if(cell == null) { //no more cells

allDone();

return;

}

coordinate = (Coordinate)cell.first; //coordinate of first atom in cell (possibly null)

}