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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 Tim Shearouse 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.generate;

import java.util.*;

import com.salesforce.jgrapht.*;

/**
 * Generates a complete graph of any size. A complete graph is a graph where every vertex shares an
 * edge with every other vertex. If it is a directed graph, then edges must always exist in both
 * directions. On a side note, a complete graph is the least efficient possible graph in terms of
 * memory and cpu usage. Note: This contructor was designed for a simple undirected or directed
 * graph. It will act strangely when used with certain graph types, such as undirected multigraphs.
 * Note, though, that a complete undirected multigraph is rather senseless -- you can keep adding
 * edges and the graph is never truly complete.
 *
 * @param  the graph vertex type
 * @param  the graph edge type
 *
 * @author Tim Shearouse
 * @since Nov 02, 2008
 */
public class CompleteGraphGenerator
    implements GraphGenerator
{
    private int size;

    /**
     * Construct a new CompleteGraphGenerator.
     *
     * @param size number of vertices to be generated
     *
     * @throws IllegalArgumentException if the specified size is negative.
     */
    public CompleteGraphGenerator(int size)
    {
        if (size < 0) {
            throw new IllegalArgumentException("must be non-negative");
        }

        this.size = size;
    }

    /**
     * {@inheritDoc}
     */
    @Override
    public void generateGraph(
        Graph target, VertexFactory vertexFactory, Map resultMap)
    {
        if (size < 1) {
            return;
        }

        // Add all the vertices to the set
        for (int i = 0; i < size; i++) {
            V newVertex = vertexFactory.createVertex();
            target.addVertex(newVertex);
        }

        /*
         * We want two iterators over the vertex set, one fast and one slow. The slow one will move
         * through the set once. For each vertex, the fast iterator moves through the set, adding an
         * edge to all vertices we haven't connected to yet.
         *
         * If we have an undirected graph, the second addEdge call will return nothing; it will not
         * add a second edge.
         */
        Iterator slowI = target.vertexSet().iterator();
        Iterator fastI;

        while (slowI.hasNext()) { // While there are more vertices in the set

            V latestVertex = slowI.next();
            fastI = target.vertexSet().iterator();

            // Jump to the first vertex *past* latestVertex
            while (fastI.next() != latestVertex) {
                ;
            }

            // And, add edges to all remaining vertices
            V temp;
            while (fastI.hasNext()) {
                temp = fastI.next();
                target.addEdge(latestVertex, temp);
                target.addEdge(temp, latestVertex);
            }
        }
    }
}

// End CompleteGraphGenerator.java