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/*
* Copyright (c) 2003, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code 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
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/*
* @test
* @bug 4339792
* @summary Basic test for Collections.disjoint
* @author Josh Bloch
* @key randomness
*/
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
import java.util.List;
import java.util.Random;
public class Disjoint {
static final int N = 20;
public static void main(String[] args) {
// Make an array of lists each of which shares a single element
// with its "neighbors," and no elements with other lists in the array
Random rnd = new Random();
List[] lists = new List[N];
int x = 0;
for (int i = 0; i < N; i++) {
int size = rnd.nextInt(10) + 2;
List<Integer> list = new ArrayList<>(size);
for (int j = 1; j < size; j++)
list.add(x++);
list.add(x);
Collections.shuffle(list);
lists[i] = list;
}
for (int i = 0; i < N; i++) {
for (int j = 0; j < N; j++) {
boolean disjoint = (Math.abs(i - j) > 1);
List<Integer> a = (List<Integer>) lists[i];
List<Integer> b = (List<Integer>) lists[j];
if (Collections.disjoint(a, b) != disjoint)
throw new RuntimeException("A: " + i + ", " + j);
if (Collections.disjoint(new HashSet<Integer>(a), b)
!= disjoint)
throw new RuntimeException("B: " + i + ", " + j);
if (Collections.disjoint(new HashSet<Integer>(a),
new HashSet<Integer>(b)) != disjoint)
throw new RuntimeException("C: " + i + ", " + j);
}
}
}
}
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