1/*
2 * Copyright (c) 2017, 2017, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23package org.graalvm.util;
24
25/**
26 * Unmodifiable memory efficient set data structure.
27 */
28public interface UnmodifiableEconomicSet<E> extends Iterable<E> {
29
30    boolean contains(E element);
31
32    int size();
33
34    boolean isEmpty();
35
36    default E[] toArray(E[] target) {
37        if (target.length != size()) {
38            throw new UnsupportedOperationException("Length of target array must equal the size of the set.");
39        }
40
41        int index = 0;
42        for (E element : this) {
43            target[index++] = element;
44        }
45
46        return target;
47    }
48}
49