package nabble.model;

import java.util.NoSuchElementException;
import fschmidt.util.java.Filter;


public final class FilteredNodeIterator extends NodeIterator<Node> {
	private final NodeIterator<? extends Node> iter;
	private final Filter<Node> filter;
	private Node next = null;

	public FilteredNodeIterator(NodeIterator<? extends Node> iter,Filter<Node> filter) {
		this.iter = iter;
		this.filter = filter;
	}

	public boolean hasNext() {
		while( next == null && iter.hasNext() ) {
			Node node = iter.next();
			if( filter.ok(node) )
				next = node;
		}
		return next != null;
	}

	public Node next() throws NoSuchElementException {
		if( !hasNext() )
			throw new NoSuchElementException();
		Node node = next;
		next = null;
		return node;
	}

	public void close() {
		iter.close();
	}

}