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This project contains the apt processor that implements all the checks enumerated in @Verify. It is a self contained, and shaded jar.

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/*
 * (C) Copyright 2003-2017, by Barak Naveh and Contributors.
 *
 * JGraphT : a free Java graph-theory library
 *
 * This program and the accompanying materials are dual-licensed under
 * either
 *
 * (a) the terms of the GNU Lesser General Public License version 2.1
 * as published by the Free Software Foundation, or (at your option) any
 * later version.
 *
 * or (per the licensee's choosing)
 *
 * (b) the terms of the Eclipse Public License v1.0 as published by
 * the Eclipse Foundation.
 */
package com.salesforce.jgrapht.traverse;

import java.util.*;

import com.salesforce.jgrapht.*;

/**
 * A breadth-first iterator for a directed and an undirected graph. For this iterator to work
 * correctly the graph must not be modified during iteration. Currently there are no means to ensure
 * that, nor to fail-fast. The results of such modifications are undefined.
 *
 * @param  the graph vertex type
 * @param  the graph edge type
 *
 * @author Barak Naveh
 * @since Jul 19, 2003
 */
public class BreadthFirstIterator
    extends CrossComponentIterator
{
    private Deque queue = new ArrayDeque<>();

    /**
     * Creates a new breadth-first iterator for the specified graph.
     *
     * @param g the graph to be iterated.
     */
    public BreadthFirstIterator(Graph g)
    {
        this(g, null);
    }

    /**
     * Creates a new breadth-first iterator for the specified graph. Iteration will start at the
     * specified start vertex and will be limited to the connected component that includes that
     * vertex. If the specified start vertex is null, iteration will start at an
     * arbitrary vertex and will not be limited, that is, will be able to traverse all the graph.
     *
     * @param g the graph to be iterated.
     * @param startVertex the vertex iteration to be started.
     */
    public BreadthFirstIterator(Graph g, V startVertex)
    {
        super(g, startVertex);
    }

    /**
     * @see CrossComponentIterator#isConnectedComponentExhausted()
     */
    @Override
    protected boolean isConnectedComponentExhausted()
    {
        return queue.isEmpty();
    }

    /**
     * @see CrossComponentIterator#encounterVertex(Object, Object)
     */
    @Override
    protected void encounterVertex(V vertex, E edge)
    {
        putSeenData(vertex, null);
        queue.add(vertex);
    }

    /**
     * @see CrossComponentIterator#encounterVertexAgain(Object, Object)
     */
    @Override
    protected void encounterVertexAgain(V vertex, E edge)
    {
    }

    /**
     * @see CrossComponentIterator#provideNextVertex()
     */
    @Override
    protected V provideNextVertex()
    {
        return queue.removeFirst();
    }
}

// End BreadthFirstIterator.java