Something

 private void nextGeneration()    {    	this.tempGrid = new Cell[xDim][yDim];    	    	   	        for(int i = 0; i < this.xDim; i++)        {            for(int j = 0; j < this.yDim; j++)            {            	Cell c = new Cell(i, j);            	c.setAlive(this.grid[i][j].alive);                this.tempGrid[i][j] = c;                }        }              	    	// Nächste Runde berechnen        for(int i = 0; i < this.yDim; i++)        {            for(int j = 0; j < this.xDim; j++)            {                if(???????.???????.??????checkRtol(i, j) == true)<----das da!!!                   this.grid[i][j].setAlive(true);                else                   this.grid[i][j].setAlive(false);            }        }                        }