Breadth first

bfs.java

	    private NumberNode firstNumber(AbstractNode node) {
	    	if(node == null || node.children() == 0)
	    		return null;
	    	
	    	for(AbstractNode n : node) {
	    		if(n instanceof NumberNode)
	    			return (NumberNode) n;
	    	}
	    	
	    	for(AbstractNode n : node) {
	    		NumberNode n1 = firstNumber(n);
	    		if(n1 != null)
	    			return n1;
	    	}
	    	
	    	return null;
	    }

Is this right?