Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/* *********************************************************************** *
 * project: org.matsim.*
 * CollectionUtils.java
 *                                                                         *
 * *********************************************************************** *
 *                                                                         *
 * copyright       : (C) 2013 by the members listed in the COPYING,        *
 *                   LICENSE and WARRANTY file.                            *
 * email           : info at matsim dot org                                *
 *                                                                         *
 * *********************************************************************** *
 *                                                                         *
 *   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 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *   See also COPYING, LICENSE and WARRANTY file                           *
 *                                                                         *
 * *********************************************************************** */

import java.util.ArrayList;

import java.util.List;

import java.util.Random;

public class Main {
    public static <T> List<T> getRandomDistinctElements(final Random random, final List<T> list,
            final int nElements) {
        if (list.size() < nElements)
            throw new IllegalArgumentException("cannot sample " + nElements + " elements from " + list.size());

        // TODO: avoid creating "bowl" collection
        final List<T> bowl = new ArrayList<T>(list);
        final List<T> sample = new ArrayList<T>(nElements);

        for (int i = 0; i < nElements; i++) {
            sample.add(bowl.remove(random.nextInt(bowl.size())));
        }

        return sample;
    }
}