Java Set Union union(final Iterable> elements)

Description

union

License

Open Source License

Declaration

public static <T> Set<T> union(final Iterable<Set<T>> elements) 

Method Source Code

//package com.java2s;
/**/*from   w  w w .j  a v a2  s.  c o m*/
 * Copyright (C) 2013
 * by 52 North Initiative for Geospatial Open Source Software GmbH
 *
 * Contact: Andreas Wytzisk
 * 52 North Initiative for Geospatial Open Source Software GmbH
 * Martin-Luther-King-Weg 24
 * 48155 Muenster, Germany
 * info@52north.org
 *
 * This program is free software; you can redistribute and/or modify it under
 * the terms of the GNU General Public License version 2 as published by the
 * Free Software Foundation.
 *
 * This program is distributed WITHOUT ANY WARRANTY; even without 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 (see gnu-gpl v2.txt). If not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA or
 * visit the Free Software Foundation web page, http://www.fsf.org.
 */

import java.util.Collections;

import java.util.HashSet;

import java.util.Set;

public class Main {
    public static <T> Set<T> union(final Set<T>... elements) {
        return ((elements.length == 0) ? Collections.<T> emptySet()
                : new HashSet<T>(elements.length * elements[0].size()) {
                    private static final long serialVersionUID = -3161916411604210423L;
                    {
                        for (final Set<T> s : elements) {
                            addAll(s);
                        }
                    }
                });
    }

    public static <T> Set<T> union(final Iterable<Set<T>> elements) {
        return new HashSet<T>() {
            private static final long serialVersionUID = -3161916411604210423L;
            {
                for (final Set<T> s : elements) {
                    addAll(s);
                }
            }
        };
    }
}

Related

1. union(final Set set1, final Set set2)
2. union(final Set... elements)
3. union(Set one, Set two)
4. union(Set a, Set b)