1 /* 2 * Copyright (c) 2003, 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 */ 23 24 /* 25 * @test 26 * @bug 4339792 27 * @summary Basic test for Collections.disjoint 28 * @author Josh Bloch 29 * @key randomness 30 */ 31 32 import java.util.*; 33 34 public class Disjoint { 35 final static int N = 20; 36 37 public static void main(String args[]) { 38 // Make an array of lists each of which shares a single element 39 // with its "neighbors," and no elements with other lists in the array 40 Random rnd = new Random(); 41 List[] lists = new List[N]; 42 int x = 0; 43 for (int i = 0; i < N; i++) { 44 int size = rnd.nextInt(10) + 2; 45 List<Integer> list = new ArrayList<Integer>(size); 46 for (int j = 1; j < size; j++) 47 list.add(x++); 48 list.add(x); 49 Collections.shuffle(list); 50 51 lists[i] = list; 52 } 53 54 for (int i = 0; i < N; i++) { 55 for (int j = 0; j < N; j++) { 56 boolean disjoint = (Math.abs(i - j) > 1); 57 List<Integer> a = (List<Integer>) lists[i]; 58 List<Integer> b = (List<Integer>) lists[j]; 59 60 if (Collections.disjoint(a, b) != disjoint) 61 throw new RuntimeException("A: " + i + ", " + j); 62 if (Collections.disjoint(new HashSet<Integer>(a), b) 63 != disjoint) 64 throw new RuntimeException("B: " + i + ", " + j); 65 if (Collections.disjoint(new HashSet<Integer>(a), 66 new HashSet<Integer>(b)) != disjoint) 67 throw new RuntimeException("C: " + i + ", " + j); 68 } 69 } 70 } 71 }