1 /* 2 * Copyright (c) 2017, 2018, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * The Universal Permissive License (UPL), Version 1.0 6 * 7 * Subject to the condition set forth below, permission is hereby granted to any 8 * person obtaining a copy of this software, associated documentation and/or 9 * data (collectively the "Software"), free of charge and under any and all 10 * copyright rights in the Software, and any and all patent rights owned or 11 * freely licensable by each licensor hereunder covering either (i) the 12 * unmodified Software as contributed to or provided by such licensor, or (ii) 13 * the Larger Works (as defined below), to deal in both 14 * 15 * (a) the Software, and 16 * 17 * (b) any piece of software and/or hardware listed in the lrgrwrks.txt file if 18 * one is included with the Software each a "Larger Work" to which the Software 19 * is contributed by such licensors), 20 * 21 * without restriction, including without limitation the rights to copy, create 22 * derivative works of, display, perform, and distribute the Software and make, 23 * use, sell, offer for sale, import, export, have made, and have sold the 24 * Software and the Larger Work(s), and to sublicense the foregoing rights on 25 * either these or other terms. 26 * 27 * This license is subject to the following condition: 28 * 29 * The above copyright notice and either this complete permission notice or at a 30 * minimum a reference to the UPL must be included in all copies or substantial 31 * portions of the Software. 32 * 33 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 34 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 35 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 36 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 37 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 38 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE 39 * SOFTWARE. 40 */ 41 package jdk.internal.vm.compiler.collections; 42 43 /** 44 * Unmodifiable memory efficient set data structure. 45 * 46 * @since 1.0 47 */ 48 public interface UnmodifiableEconomicSet<E> extends Iterable<E> { 49 50 /** 51 * Returns {@code true} if this set contains a mapping for the {@code element}. 52 * 53 * @since 1.0 54 */ 55 boolean contains(E element); 56 57 /** 58 * Returns the number of elements in this set. 59 * 60 * @since 1.0 61 */ 62 int size(); 63 64 /** 65 * Returns {@code true} if this set contains no elements. 66 * 67 * @since 1.0 68 */ 69 boolean isEmpty(); 70 71 /** 72 * Stores all of the elements in this set into {@code target}. An 73 * {@link UnsupportedOperationException} will be thrown if the length of {@code target} does not 74 * match the size of this set. 75 * 76 * @return an array containing all the elements in this set. 77 * @throws UnsupportedOperationException if the length of {@code target} does not equal the size 78 * of this set. 79 * @since 1.0 80 */ 81 default E[] toArray(E[] target) { 82 if (target.length != size()) { 83 throw new UnsupportedOperationException("Length of target array must equal the size of the set."); 84 } 85 86 int index = 0; 87 for (E element : this) { 88 target[index++] = element; 89 } 90 91 return target; 92 } 93 }