Java Collection Random Element chooseElement(Collection elements, T alternative)

Description

choose Element

License

Open Source License

Declaration

public static <T> T chooseElement(Collection<T> elements, T alternative) 

Method Source Code

//package com.java2s;
/*/*  w w w. ja va2  s .c o m*/
 * Copyright (C) 2011 Pavel Fatin <http://pavelfatin.com>
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import java.util.Collection;
import java.util.Random;

public class Main {
    private static final Random _random = new Random();

    public static <T> T chooseElement(T[] elements) {
        return chooseElement(elements, null);
    }

    public static <T> T chooseElement(Collection<T> elements, T alternative) {
        return chooseElement((T[]) (elements.toArray()), alternative);
    }

    public static <T> T chooseElement(T[] elements, T alternative) {
        if (elements.length == 0) {
            return alternative;
        } else {
            int choiceIndex = _random.nextInt(elements.length);
            return elements[choiceIndex];
        }
    }
}

Related

1. chooseRandomThing(Collection possibleroutes)
2. chooseWithoutCheck(Collection collection, long seed)
3. generateMetricsDataWithAllWrongTypes(String metricPostfix, boolean generateRandomTenant, long collectionTime)
4. generateMetricsDataWithPartialWrongTypes(String metricPostfix, boolean generateRandomTenant, long collectionTime)