GridIterator.java

package model;

import java.util.Iterator;

public class GridIterator<T> implements Iterator<T> {
  private int rowIndex;
  private int columnIndex;
  private final Grid<T> grid;

  GridIterator(Grid grid) {
    this.rowIndex = 0;
    this.columnIndex = 0;
    this.grid = grid;
  }

  @Override
  public boolean hasNext() {
    return columnIndex < grid.getNumberOfColumns() && rowIndex < grid.getNumberOfRows();
  }

  @Override
  public T next() {
    final T result = grid.getSquare(rowIndex, columnIndex);
    columnIndex = (columnIndex +1) % grid.getNumberOfColumns();
    if(columnIndex == 0){
      rowIndex++;
    }
    return result;
  }
}