Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

import java.util.*;

public class Main {
    /**
     * Returns a three-element array of mutable {@code List}s:
     * <ol>
     *    </li>
     *      the intersection of {@code a} and {@code b}
     *    <li>
     *    </li>
     *      the {@code a} - {@code b} difference
     *    <li>
     *    </li>
     *      the {@code b} - {@code a} difference
     *    <li>
     * </ol>
     *
     * @param       comparator
     *          a comparator to sort results, or {@code null} to remain
     *          unsorted
     */
    public static <T> List<T>[] getIntersectAndDiffs(Collection<? extends T> a, Collection<? extends T> b,
            Comparator<T> comparator) {

        int aSize = a.size();
        List<T> aDiff = new ArrayList<T>(aSize);
        aDiff.addAll(a);

        int bSize = b.size();
        List<T> bDiff = new ArrayList<T>(bSize);
        bDiff.addAll(b);

        if (comparator != null) {
            Collections.sort(aDiff, comparator);
            Collections.sort(bDiff, comparator);
        }

        List<T> abInter = new ArrayList<T>(Math.min(aSize, bSize));

        for (int i = aDiff.size() - 1; i >= 0; i--) {
            T element = aDiff.get(i);

            int index = comparator == null ? bDiff.indexOf(element)
                    : Collections.binarySearch(bDiff, element, comparator);

            if (index != -1) {
                bDiff.remove(index);
                aDiff.remove(i);
                abInter.add(element);
            }
        }

        @SuppressWarnings({ "unchecked" })
        List<T>[] array = (List<T>[]) new List[] { abInter, aDiff, bDiff };

        return array;
    }

    public static <T> void addAll(Collection<T> collection, T... array) {
        for (T t : array) {
            collection.add(t);
        }
    }
}