Main.java Source code

Introduction

Here is the source code for Main.java

Source

//package com.java2s;
/*
 * Copyright (C) 2011 Francesco Feltrinelli <first_name DOT last_name AT gmail DOT 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.lang.reflect.Array;

import java.util.Collection;
import java.util.Iterator;

public class Main {
    @SuppressWarnings("unchecked")
    public static <S, D extends S> D[] downcastToArray(Collection<S> source, Class<D> destClass) {
        D[] dest = (D[]) Array.newInstance(destClass, source.size());
        Iterator<S> it = source.iterator();
        for (int i = 0; i < dest.length; i++) {
            S s = it.next();
            if (destClass.isAssignableFrom(s.getClass()))
                dest[i] = (D) s;
            else
                throw new IllegalArgumentException("Could not downcast element from class "
                        + s.getClass().getSimpleName() + " to " + destClass.getSimpleName());
        }
        return dest;
    }
}